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A systematic literature review and meta-analysis was conducted to evaluate whether the administration of an oxytocin receptor antagonist (OTR-a) around embryo transfer is associated with live birth and pregnancy achievement in IVF treatment. Multiple databases were searched for randomized controlled trials (RCT) comparing the outcome of IVF treatment with administration of an OTR-a before, during or after embryo transfer versus administration of placebo/nil. The literature search identified 11 eligible RCT. The active compound was intravenous atosiban (n = 7), subcutaneous barusiban (n = 1) and oral nolasiban (n = 3). Clinical pregnancy rate was significantly higher in women receiving an OTR-a around embryo transfer (relative risk [RR] 1.31, 95% confidence interval [CI] 1.13–1.51, P = 0.0002, I2 = 61%, n = 11 studies, n = 3611); however, live birth rate was not statistically significantly affected (RR 1.09, 95% CI 0.98–1.20, P = 0.11, I2 = 25%, n = 5 studies, n = 2765). A sensitivity analysis on low risk of bias studies likewise indicates a higher clinical pregnancy chance (RR 1.11, 95% CI 1.01–1.22, P = 0.03, I2 = 5%, n = 5 RCT, n = 2765). OTR-a administration in IVF treatment has the potential to increase IVF efficacy, although the treatment effects observed so far are small and have not been sufficiently corroborated.

Background Embryo transfer without difficulty in a patient with cervical stenosis can be a great challenge for in vitro fertilization (IVF). We report a successful pregnancy following a frozen thawed embryo transfer after administration of an oxytocin antagonist at the same time as using a Foley catheter with cotton swab in a patient with refractory cervical stenosis. Case presentation A 40-year-old woman undergoing IVF. The patient’s previous embryo transfers were difficult. For every transfer, uterine manipulation was needed, force was required, and dilatation was necessary. A Foley catheter with a cotton swab was inserted into the cervical canal, atosiban was administered at the same time, and the Foley catheter was removed immediately before embryo transfer. A smooth transfer was performed without bleeding, force, uterine manipulation, or cervical dilator. The patient became pregnant and delivered by cesarean section at term. Conclusion This method is effective in performing atraumatic embryo transfer in patients with cervical stenosis.

Objectives: This study aimed to generate baseline evidence regarding the effectiveness of atosiban in delaying delivery by ≥48 hours among pregnant women presenting with threatened preterm labour (TPL). The secondary objective was to assess the relationship between atosiban success and various perinatal factors and neonatal outcomes. Methods: This retrospective study was conducted between June 2008 and May 2018 at the Sultan Qaboos University Hospital, Muscat, Oman. The medical records of all pregnant women who received atosiban between 24–34 gestational weeks for TPL during this period were reviewed. Results: A total of 159 women were included in the study. Atosiban was successful in delaying delivery by ≥48 hours in 130 cases (81.8%). Approximately half of the women (50.9%) achieved uterine quiescence in

Preclinical and clinical evidence suggests that exogenous administration of oxytocin (OT) may hold promise as a therapeutic strategy for reducing heavy alcohol drinking. However, it remains unknown whether these effects are mediated by stimulation of endogenous sources of OT and signaling at oxytocin receptors (OTR) in brain or in the periphery. To address this question, we employed a targeted chemogenetic approach to examine whether selective activation of OT-containing neurons in the paraventricular nucleus of the hypothalamus (PVN) alters alcohol consumption in a binge-like drinking (“Drinking-in-the-Dark”; DID) model. Adult male Oxt-IRES-Cre mice received bilateral infusion of a Cre-dependent virus containing an excitatory DREADD (AAV8-hSyn-DIO-hM3Dq-mCherry) or control virus (AAV8-hSyn-DIO-mCherry) into the PVN. Chemogenetic activation of PVN(OT+) neurons following clozapine-N-oxide injection reduced binge-like alcohol drinking in a similar manner as systemic administration of the neuropeptide. Pretreatment with a brain-penetrant OTR antagonist (L-368,899) reversed this effect while systemic administration of a peripherally restricted OTR antagonist (Atosiban) did not alter reduced alcohol drinking following chemogenetic activation of PVN(OT+) neurons. Altogether, these data are the first to demonstrate that targeted activation of hypothalamic (endogenous) OT reduces alcohol consumption, providing further evidence that this neuropeptide plays a role in regulation of alcohol self-administration behavior. Further, results indicate that the ability OT to reduce alcohol drinking is mediated by signaling at OTR in the brain.

Background Increased insulin production and secretion by pancreatic β-cells are important for ensuring the high insulin demand during gestation. However, the underlying mechanism of β-cell adaptation during gestation or gestational diabetes mellitus (GDM) remains unclear. Oxytocin is an important physiological hormone in gestation and delivery, and it also contributes to the maintenance of β-cell function. The aim of this study was to investigate the role of oxytocin in β-cell adaptation during pregnancy. Methods The relationship between the blood oxytocin level and pancreatic β-cell function in patients with GDM and healthy pregnant women was investigated. Gestating and non-gestating mice were used to evaluate the in vivo effect of oxytocin signal on β-cells during pregnancy. In vitro experiments were performed on INS-1 insulinoma cells. Results The blood oxytocin levels were lower in patients with GDM than in healthy pregnant women and were associated with impaired pancreatic β-cell function. Acute administration of oxytocin increased insulin secretion in both gestating and non-gestating mice. A 3-week oxytocin treatment promoted the proliferation of pancreatic β-cells and increased the β-cell mass in gestating but not non-gestating mice. Antagonism of oxytocin receptors by atosiban impaired insulin secretion and induced GDM in gestating but not non-gestating mice. Oxytocin enhanced glucose-stimulated insulin secretion, activated the mitogen-activated protein kinase pathway, and promoted cell proliferation in INS-1 cells. Conclusions These findings provide strong evidence that oxytocin is needed for β-cell adaptation during pregnancy to maintain β-cell function, and the lack of oxytocin could be associated with the risk of GDM.

Background: Lannea acida (Anacardiaceae), commonly called Kikié in the Noun division (West-Cameroon), is a tree whose bark is used locally to solve difficult childbirth. This study aimed to evaluate the in vitro uterotonic effects of aqueous and methanolic extracts of L. acida in female Wistar rats. Uterine strips isolated from female rats pretreated (48h) with oestradiol (5μg) were mounted in a single-organ bath containing a well aerated and thermostated De Jalon solution (37°C). The effects of L. acida extracts were recorded in a non-cumulative manner after application. The effect of the methanolic extract (the most active extract) was monitored in the presence of atosiban (a competitive antagonist of oxytocin receptors), atropine (a specific type 3 muscarinic receptor antagonist), nifedipine (an L-type calcium channel antagonist) and 2-Aminoethoxydiphenyl borate (2-ADB, a specific antagonist of inositol 1,4,5-triphosphate receptors type 1), and in calcium-free medium containing EGTA. Results: L. acidainduced uterine contraction in a concentration-dependent manner with the methanolic extract (1.506 ± 0.032 gf) being the most effective. Administration of atosiban (2 μmol/l), atropine (1 μmol/l), nifedipine (5 μmol), 2-APB (100 μmol), and calcium free medium containing EGTA (2 mmol) reduced the contractile effect of L. acida. Complete inhibition was observed with nifedipine, 2-APB, and calcium free medium containing EGTA.Conclusions: These results suggest that L. acida possesses an uterotonic effect mediated through oxytocin receptors with mobilization of extracellular calcium.

Aims: To assess the efficacy and fetomaternal safety of atosiban among Indian pregnant women presenting with preterm labor. Study Design: Prospective, open-label, multicentric, non-comparative, phase-IV clinical study. Place and Duration of Study: Department of Obstetrics and Gynaecology at nine hospitals across India from October 2016 to December 2019. Methodology: A total of 212 pregnant women admitted with preterm labour between 24 and 36 weeks of gestation were administered intravenous atosiban up to 48 hours. Efficacy was defined as the successful delay of delivery without the need of an additional or alternative tocolytic agent for 72 hours. Safety was evaluated by recording the occurrence of adverse events in the mother, fetus and neonate. Results: Tocolytic efficacy of Atosiban was 84.88% at 48 hours and 74.15% at day 7 without additional tocolytic agent or retreatment after 48 hours. The mean number of days gained after the start of atosiban tocolysis were 29.15 ± 1.82 days with mean gestational age at delivery of 35.1 ± 3.33 weeks. Atosiban reduced the frequency of contractions from 4.3 ± 1.47 to 0.67 ± 1.13 contractions/30 min at 72 hours. The proportion of neonates with birth weights more than 2,500 gm was 41.67%. A total of 205 neonates out of 216 (94.95%) had APGAR score more than 7 after 5 minute. Atosiban successfully delayed the labour in 92.31% (n=13) of “Twin pregnancy” patients for 48 hours and beyond 7 days in 9 patients (69.2%). There were no serious adverse events reported. Conclusions: In patients with threatened preterm birth, 48 hour tocolysis with atosiban was found to be safe and effective in preventing imminent preterm birth even when it was a twin pregnancy or associated with co-morbidities. Atosiban showed favorable side effects profile and improved the perinatal outcomes. Clinical Trial Registry of India Number: CTRI/2017/03/008065

Objective: To compare the efficacy of atosiban with conventional treatment of the threatened preterm labor. Materials and methods: All the data of pregnant women with threatened preterm labor from January 1 to December 31, 2017, who received atosiban were collected. Pregnant women with conventional treatment (including β-agonists, indomethacin, magnesium sulphate and calcium channel blockers, alone or in combination) were used as control. Results: The proportion of women not requiring an alternative tocolytic treatment within 48 h and remaining undelivered was significantly higher in atosiban treatment group (89.3%; n = 25/28) compared with conventional treatment (24.2%; n = 8/33) (P

Objective The aim of this study is to assess the efficacy and safety of retosiban in spontaneous preterm labor (sPTL). Study Design Two multicenter, randomized, and double-blind trials compared retosiban with placebo and retosiban with atosiban in women with a singleton pregnancy and intact membranes in sPTL at 24 to 336/7 weeks' gestation. Coprimary endpoints in the placebo-controlled trial were time to delivery (TTD) or treatment failure (whichever occurred first) and neonatal composite morbidity and mortality. The primary endpoint of the atosiban comparator trial was TTD. Results The trials were terminated early because of slow recruitment. The placebo-controlled trial enrolled 23 participants (February 2016–July 2017; 2.6% of target);the atosiban-comparator trial enrolled 97 (March 2015–August 2017; 29% of target). Baseline participant characteristics were similar between treatments. In the placebo-controlled trial, mean gestational ages at randomization were 30.8 (retosiban, n = 10) and 30.5 weeks (placebo, n = 13), and mean times to delivery/treatment failure were 18.9 days (retosiban) and 11.1 days (placebo). Two and four neonates in the retosiban and placebo groups, respectively, had ≥1 component of the neonatal composite endpoint. In the atosiban-comparator trial, mean gestational age at randomization was 31.5 weeks (for both retosiban, n = 47, and atosiban, n = 50), and adjusted mean TTDs were 32.51 days (retosiban) and 33.71 days (atosiban; p > 0.05). Adverse events were no more common with retosiban than placebo or atosiban. Conclusion Despite considerable efforts to conduct two adequate and well-controlled studies in patients with sPTL, both studies were unable to recruit effectively and consequently terminated prematurely. Key factors negatively affecting participation were patient and physician resistance to use of a placebo comparator, lack of investigator consensus on diagnostic criteria and acceptance of protocol procedures, and ethics committee decisions. Meaningful cooperation between pharmaceutical companies, regulatory authorities, and the obstetric community is essential for future development of drugs to treat sPTL.

To assess the efficacy of atosiban versus ritodrine as tocolytics in external cephalic version (ECV).A prospective comparative trial was carried out in a tertiary hospital. 430 women with singleton breech pregnancies ≥36 weeks were recruited for ECV, 215 with ritodrine and 215 with atosiban as tocolytic agents. The efficacy, complications and perinatal outcomes were compared between both groups. The associations between variables were analyzed using the chi-square test (χThe overall ECV success rate was 47.9% (206/430), 46.0% in the atosiban group (99/215) and 49.8% in the ritodrine group (107/215). This difference showed no statistical significance (Atosiban and ritodrine showed similar efficacy as tocolytic agents in ECV, with no differences in complications and perinatal outcomes between these two agents.

Background and objectives: The aim of this study was to investigate the contractile effects of oxytocin (OT) in human detrusor muscle in in vitro conditions.Material and Methods: Human detrusor mus...

We assessed the effect of atosiban on pregnancy outcomes following in vitro fertilization (IVF) treatment among infertile women requiring different numbers of embryo transfer (ET) cycles (i.e., one, two, and more than two ET cycles). A longitudinal cohort study was conducted by utilizing the data from the Assisted Reproductive Technology Center in a university tertiary hospital during 2007-2017. Patients receiving IVF treatment with at least one ET cycle were included. Pregnancy outcomes following IVF treatment, including biochemical, clinical, and ongoing pregnancies, were investigated. The association between atosiban and IVF pregnancy was assessed using logistic generalized estimating equation models, with adjustment for time-varying clinical characteristics (e.g., maternal age) across multiple ET cycles for an individual. 403 women with 838 ET cycles were included, where 165 patients required one ET cycle, 133 patients required two ET cycles (a total of 266 ET cycles), and 105 patients required more than two ET cycles (a total of 407 ET cycles). Atosiban use was not significantly associated with pregnancy outcomes among all study infertile women undergoing IVF treatment. However, the results for women requiring more than two ET cycles showed significantly increased pregnancy rates associated with atosiban use (i.e., odds ratios [95% confidence interval] of 4.40 [1.52, 12.73] and 2.85 [1.45, 5.60] for clinical and ongoing pregnancies, respectively). This association was not observed for the women requiring only one or two ET cycles. Atosiban is a potential treatment for enhancing IVF pregnancy, especially among infertile women requiring more than two ET cycles.

Objective To estimate the effectiveness of Atosiban in improving the outcome after embryo transfer. The effectiveness of embryo transfer per cycle is still relatively low. One possible explanation might be uterine contractility that expels the transferred embryos. Atosiban improved the outcome of embryo transfer by reducing uterine contractility. Methods Data sources: A systematic review of papers in English using MEDLINE and EMBASE (1990-2019). Search terms included Atosiban, embryo transfer. Study selection: We included studies that compared the outcomes of embryo transfer with Atosiban and a control group. Data Extracting: Independent extraction of papers by two authors, using predefined data fields, including study quality indicators. Results All pooled analyses were based on a fixed-effect model. Four randomised controlled trials, including 1,025 women, and two non-randomised trials, including 686 patients, met our inclusion criteria. In both studies, the heterogeneity was moderate. Atosiban increased clinical pregnancy rates regardless of the indication for ART or type of embryo transferred. Pooled OR in randomized controlled trials reached 1.47 (1.18-1.82), and in non-randomised controlled trials it reached 1.50 (95% CI 1.10-2.05). Conclusion Atosiban appears to increase the clinical pregnancy rates in women undergoing embryo transfer.

Preterm premature rupture of membranes (PPROM) occurs in up to 3% of all pregnancies. Only few comparative studies have investigated potential risks and benefits between different tocolytic substances in women with PPROM. The aim of this study was to compare the neonatal short term outcome after tocolysis with Atosiban or Hexoprenaline in women with PPROM. This is a retrospective observational cohort study of women with PPROM between 24 and 32 weeks of gestation comparing neonatal and maternal outcome after tocolysis with atosiban or hexoprenaline. Outcome parameters were short term neonatal outcome, maternal tocolytic efficacy, effectiveness and tolerability and neonatal neurodevelopmental long-term outcome. Continuous variables were compared using t-Test or Mann–Whitney U test, as appropriate. For categorical variables Chi-square after Pearson and Fisher exact-test were used to compare the two groups. 93 women were included into this study with 42 women receiving hexoprenaline and 51 women receiving atosiban as primary tocolytic treatment. Mean gestational age was 29 weeks in both groups at the time PPROM. No differences were found for any short term neonatal outcome parameters, tocolytic efficacy, effectiveness and tolerability and neonatal neurodevelopmental long-term outcome. Both hexoprenaline and atosiban do not affect the short and long term neonatal outcome in women with PPROM for the time of lung maturation.

Objective To evaluate the impact of atosiban as a tocolytic agent in patients treated with the fetoscopic endotracheal occlusion (FETO) procedure due to congenital diaphragmatic hernia (CDH). As premature birth after fetoscopy remains a serious concern, an effort to reduce prematurity is required. Methods A total of 43 patients with severe CDH treated with FETO were enrolled in this study. The study group consisted of 22 patients who received atosiban during the FETO procedure and a control group of 21 patients who did not receive atosiban during the FETO procedure. Demographic data, gestational age (GA) at delivery, cervical length and GA at premature rupture of membranes (PROM) were evaluated. Results The GA at delivery was significantly different between the two groups studied. The median GA at delivery was 32.6 and 34.5 weeks in the no-atosiban vs. atosiban groups, respectively (P = 0.013). The median cervical length was 29.9 and 31.2 mm for the no-atosiban and atosiban groups, respectively, and was not statistically significant (P = 0.28). There were no significant correlations between groups for the occurrence of PROM, GA at the time of PROM, duration of the procedures, parity, maternal body mass index (BMI) or age. In the univariate linear regression model, the only factor independently associated with GA at delivery was the use of atosiban during FETO procedures (β = 0.375; P Conclusion In cases of severe CDH treated with FETO, the use of atosiban as a tocolytic agent during the procedure prolonged pregnancy by 2 weeks. Cervical length, duration of FETO or maternal characteristics were not associated with GA at delivery.

Research question What is the in-vitro effect of oxytocin receptor (OTR) antagonism on parameters of receptivity in human endometrial explants and endometrial stromal cell lines cultured in oestradiol-rich conditions mimicking ovarian stimulation? Design Experimental in-vitro study on endometrial tissue explants collected by aspiration biopsy from 30 women undergoing fertility treatment and cultured endometrial tHESC cell line. The study examined the effects of high oestradiol, oxytocin and OTR antagonist on parameters of decidualization (cell viability and prolactin secretion) as well as cyclooxygenase-1/2 (COX-1/2) activity and prostaglandin F2α (PGF2α) secretion. Changes in expression of OXTR and COX-2 genes were examined using quantitative polymerase chain reaction (qPCR). Results In experiments on cultured endometrial cell line, high oestradiol and oxytocin similarly limited the viability of cells. In cultured endometrial explants both also decreased the secretion of prolactin (a marker of decidualization) and augmented endometrial COX-2 activity and formation of PGF2α. Oxytocin antagonist atosiban was confirmed to reverse the above effects, both in the endometrial line and endometrial explants. Addition of atosiban to cultures acted analogously in experiments employing both oxytocin and high oestradiol. Conclusions Oxytocin antagonist reversed the effects of high oestradiol and oxytocin on parameters related to endometrial receptivity in conditions mimicking ovarian stimulation. This might point to a novel, endometrium-related mechanism to support embryo implantation achieved by the application of oxytocin antagonist prior to embryo transfer.

Growing evidence suggests that oxytocin (OT) plays an important factor for the control of food intake, body weight, and energy metabolism in human and non-human animals. It has reported previously, the downregulation in oxytocin receptors (OTRs) expression is linked with the development of obesity, but exogenous OT reverse body weight and food intake in obese animal model. It is important to know that, whether intraperitoneal administration crosses blood brain barrier. Therefore, in the present experiment, we study the impact of intraperitoneal administration of synthetic OT 0.0116 mg/kg and antagonist atosiban (OTA) 1 mg/kg on food intake, and body weight of female mice, Mus musculus for different duration i.e. 30, 60, and 90 days. In this study, it was observed that there was significant decrease (p

BackgroundThe use of atosiban during embryo transfer (ET), an oxytocin receptor antagonist, has been demonstrated to enhance pregnancy rate among infertile patients with endometriosis. However, its efficacy has not been assessed among those with concurrent adenomyosis, which may further affect pregnancy rate.MethodsThis retrospective cohort study assessed in vitro fertilization (IVF) pregnancy, and the effect of atosiban among 34 women with both endometriosis and adenomyosis (with 66 ET cycles), compared to 34 endometriosis patients without adenomyosis (with 54 ETs) and 38 patients with tubal factor (with 56 ETs). Multivariable logistic generalized estimating equation analyses were performed to assess pregnancy outcomes with adjustment for maternal and treatment characteristics.ResultsSignificantly higher chances of biochemical pregnancy and live birth among endometriosis patients without adenomyosis versus those with both endometriosis and adenomyosis were found (odds ratios [95% confidence intervals]: 2.981 [1.307, 6.803]; p=0.009, 2.694 [1.151, 6.304]; p=0.022). A significant positive association between atosiban use and biochemical pregnancy existed among endometriosis cases without adenomyosis (a 2.43-fold [1.01, 5.89] increase in successful pregnancy; p

Background Embryo transfer (ET) is a crucial step of in vitro fertilisation (IVF) treatment, and involves placing the embryo(s) in the woman's uterus. There is a negative association between endometrial wave-like activity (contractile activities) at the time of ET and clinical pregnancy, but no specific treatment is currently used in clinical practice to counteract their effects. Oxytocin is a hormone produced by the hypothalamus and released by the posterior pituitary. Its main role involves generating uterine contractions during and after childbirth. Atosiban is the best known oxytocin antagonist (and is also a vasopressin antagonist), and it is commonly used to delay premature labour by halting uterine contractions. Other oxytocin antagonists include barusiban, nolasiban, epelsiban, and retosiban. Administration of oxytocin antagonists around the time of ET has been proposed as a means to reduce uterine contractions that may interfere with embryo implantation. The intervention involves administering the medication before, during, or after the ET (or a combination). Objectives To evaluate the effectiveness and safety of oxytocin antagonists around the time of ET in women undergoing assisted reproduction. Search methods We searched the Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, and two trials registers in March 2021; and checked references and contacted study authors and experts in the field to identify additional studies. Selection criteria We included randomised controlled trials (RCTs) of the use of oxytocin antagonists for women undergoing ET, compared with the non-use of this intervention, the use of placebo, or the use of another similar drug. Data collection and analysis We used standard methodological procedures recommended by Cochrane. Primary review outcomes were live birth and miscarriage; secondary outcomes were clinical pregnancy and other adverse events. Main results We included nine studies (including one comprising three separate trials, 3733 women analysed in total) investigating the role of three different oxytocin antagonists administered intravenously (atosiban), subcutaneously (barusiban), or orally (nolasiban). We found very low- to high-certainty evidence: the main limitations were serious risk of bias due to poor reporting of study methods, and serious or very serious imprecision. Intravenous atosiban versus normal saline or no intervention We are uncertain of the effect of intravenous atosiban on live birth rate (risk ratio (RR) 1.05, 95% confidence interval (CI) 0.88 to 1.24; 1 RCT, N = 800; low-certainty evidence). In a clinic with a live birth rate of 38% per cycle, the use of intravenous atosiban would be associated with a live birth rate ranging from 33.4% to 47.1%. We are uncertain whether intravenous atosiban influences miscarriage rate (RR 1.08, 95% CI 0.75 to 1.56; 5 RCTs, N = 1424; I² = 0%; very low-certainty evidence). In a clinic with a miscarriage rate of 7.2% per cycle, the use of intravenous atosiban would be associated with a miscarriage rate ranging from 5.4% to 11.2%. Intravenous atosiban may increase clinical pregnancy rate (RR 1.50, 95% CI 1.18 to 1.89; 7 RCTs, N = 1646; I² = 69%; low-certainty evidence), and we are uncertain whether multiple or ectopic pregnancy and other complication rates were influenced by the use of intravenous atosiban (very low-certainty evidence). Subcutaneous barusiban versus placebo One study investigated barusiban, but did not report on live birth or miscarriage. We are uncertain whether subcutaneous barusiban influences clinical pregnancy rate (RR 0.96, 95% CI 0.69 to 1.35; 1 RCT, N = 255; very low-certainty evidence). Trialists reported more mild to moderate injection site reactions with barusiban than with placebo, but there was no difference in severe reactions. They reported no serious drug reactions; and comparable neonatal outcome between groups. Oral nolasiban versus placebo Nolasiban does not increase live birth rate (RR 1.13, 95% CI 0.99 to 1.28; 3 RCTs, N = 1832; I² = 0%; high-certainty evidence). In a clinic with a live birth rate of 33% per cycle, the use of oral nolasiban would be associated with a live birth rate ranging from 32.7% to 42.2%. We are uncertain of the effect of oral nolasiban on miscarriage rate (RR 1.45, 95% CI 0.73 to 2.88; 3 RCTs, N = 1832; I² = 0%; low-certainty evidence). In a clinic with a miscarriage rate of 1.5% per cycle, the use of oral nolasiban would be associated with a miscarriage rate ranging from 1.1% to 4.3%. Oral nolasiban improves clinical pregnancy rate (RR 1.15, 95% CI 1.02 to 1.30; 3 RCTs, N = 1832; I² = 0%; high-certainty evidence), and probably does not increase multiple or ectopic pregnancy, or other complication rates (moderate-certainty evidence). Authors' conclusions We are uncertain whether intravenous atosiban improves pregnancy outcomes for women undergoing assisted reproductive technology. This conclusion is based on currently available data from seven RCTs, which provided very low- to low-certainty evidence across studies. We could draw no clear conclusions about subcutaneous barusiban, based on limited data from one RCT. Further large well-designed RCTs reporting on live births and adverse clinical outcomes are still required to clarify the exact role of atosiban and barusiban before ET. Oral nolasiban appears to improve clinical pregnancy rate but not live birth rate, with an uncertain effect on miscarriage and adverse events. This conclusion is based on a phased study comprising three trials that provided low- to high-certainty evidence. Further large, well-designed RCTs, reporting on live births and adverse clinical outcomes, should focus on identifying the subgroups of women who are likely to benefit from this intervention.

Methamphetamine (METH) is a highly neurotoxic psychoactive substance that can directly damage the central nervous system through prolonged use. Oxytocin (OT) has attracted much attention because of its neuroprotective effect. The purpose of this study was to investigate whether OT is neuroprotective against METH-induced damage in rat hippocampal neurons. Our results revealed that pre-incubation with OT significantly prevented the damage of METH to hippocampal neurons, including the decrease of mitochondrial membrane potential and the increase of ROS (reactive oxygen species). OT pre-incubation attenuated the up-regulation of Cleaved-Caspase-3 expression and the down-regulation of Bcl-2/Bax expression induced by METH. Pre-incubation with OT prevented the decrease in oxytocin receptor density and P-CREB (phosphorylation of cAMP-response element binding) expression induced by METH in rat hippocampal neurons. Moreover, Pre-incubation of atosiban (ATO) significantly prevented these changes. In conclusion, our study proved that pre-administration of OT could significantly attenuate hippocampal neuron apoptosis induced by METH. Oxytocin receptor activation is involved in the preventive effect of OT on METH-induced apoptosis in rat hippocampal neurons.

Study question Does the administration of an oxytocin-receptor antagonist around time of embryo transfer in IVF impact the likelihood to achieve a clinical pregnancy? Summary answer Administration of oxytocin-receptor antagonists around embryo transfer increases the likelihood of clinical pregnancy achievement. What is known already Uterine contractions occurring around time of embryo transfer have been described as one possible mechanism of failure of implantation of an embryo in the context of in-vitro fertilization (IVF). Hence the utilization of oxytocin-receptor antagonists was evaluated in randomized clinical trials (RCT) as a therapeutic approach. The compound Atosiban was studied by most RCTs (summarized in Huang et al. 2017). Recently further studies have become available which also investigated the novel agents Barusiban and Nolasiban. This systematic review collates the evidence of all drugs functioning as oxytocin-receptor antagonists which have been investigated in RCTs on IVF treatment so far. Study design, size, duration Multiple literature databases were searched for randomized controlled studies comparing the outcome of IVF cycles with administration of an oxytocin-receptor antagonist in the time period before, during or after embryo transfer versus placebo or nil in IVF patients. Meta-analyses were performed using standard procedures in the software program RevMan v.5.4. All analyses were done per randomized patient, wherever feasible. Participants/materials, setting, methods Eleven RCTs were identified and included in the meta-analysis. Seven utilized the agent Atosiban, one Barusiban and three Nolasiban. These drugs were administered either intravenously, subcutaneously or orally. The patient populations were heterogenous (fresh cycle, frozen-thawed cycle, endometriosis, implantation failure or general IVF-population) between trials. Only four studies reported live birth rates whereas all RCTs reported clinical pregnancy rate. Main results and the role of chance Administration of an oxytocin-receptor antagonist around embryo transfer increases the likelihood of live birth (relative risk: 1.1, 95% CI: 0.99-1.22, p = 0.06, I2=31%, four RCTs, n = 2,510). Accordingly, the ongoing pregnancy rate is increased (relative risk: 1.14, 95% CI: 1.03-1.26, p = 0.01, I2=18%, four RCTs, n = 2,510) as well as the clinical pregnancy rate (relative risk: 1.31, 95% CI: 1.13-1.51, p = 0.0002, I2=61%, eleven RCTs, n = 3,611) by administration of an oxytocin-receptor antagonist. The risk to suffer a miscarriage, however, is not influenced by an oxytocin-receptor antagonist administration (relative risk: 0.90, 95% CI: 0.72-1.12, p = 0.35, I2=0%, seven RCTs, n = 2,936). The risk of multiple pregnancy is not different between groups (relative risk: 1.05 95% CI: 0.81-1.36, p = 0.73, I2=5%, seven RCTs, n = 3,014) as is the risk for an ectopic pregnancy (relative risk: 0.88 95% CI: 0.43-1.8, p = 0.73, I2=0%, four RCTs, n = 2,714). Limitations, reasons for caution Methodological rigor is heterogenous between trials and some of the evidence is of poor quality. Evaluation of included studies is still ongoing and queries are pending. Additionally, there is heterogeneity between patient populations and definition of outcomes; only four RCTs report ongoing pregnancies and live births. Wider implications of the findings The administration of oxytocin-receptor antagonists around embryo transfer increases the pregnancy rate and may be a promising approach to enhance the likelihood to achieve a live birth per embryo transfer. Trial registration number n.a.

Ketamine is a popular recreational substance of abuse that induces persistent behavioral deficits. Although disrupted oxytocinergic systems have been considered to modulate vulnerability to developing drugs of abuse, the involvement of central oxytocin in behavioral abnormalities caused by chronic ketamine has remained largely unknown. Herein, we aimed to investigate the potential role of oxytocin in the medial prefrontal cortex (mPFC) in social avoidance and cognitive impairment resulting from repeated ketamine administration in mice. We found that ketamine injection (5 mg/kg, i.p.) for 10 days followed by a 6-day withdrawal period induced behavioral disturbances in social interaction and cognitive performance, as well as reduced oxytocin levels both at the periphery and in the mPFC. Repeated ketamine exposure also inhibited mPFC neuronal activity as measured by a decrease in c-fos-positive cells. Furthermore, direct microinjection of oxytocin into the mPFC reversed the social avoidance and cognitive impairment following chronic ketamine exposure. In addition, oxytocin administration normalized ketamine-induced inflammatory cytokines including TNF-α, IL-6, and IL-1β levels. Moreover, the activation of immune markers such as neutrophils and monocytes, by ketamine was restored in oxytocin-treated mice. Finally, the reversal effects of oxytocin on behavioral performance were blocked by pre-infusion of the oxytocin receptor antagonist atosiban into the mPFC. These results demonstrate that enhancing oxytocin signaling in the mPFC is a potential pathway to reverse social avoidance and cognitive impairment caused by ketamine, partly through inhibition of inflammatory stimulation.

At the 73rd Annual Congress of the Japan Society of Obstetrics and Gynecology, we discussed recent tocolytic treatments for the prevention of preterm birth with obstetricians from Korea and Taiwan. The rate of preterm birth in our countries has been increasing, and optimal tocolytic treatments are of great concern. Ritodrine hydrochloride was the first available drug for tocolysis in our countries and is often administered for over 48 h, although it is not recommended for maintenance therapy in Western countries. Meanwhile, there are differences in the use of other tocolytic drugs, based on approval of the drugs and the health insurance systems. Nifedipine and atosiban have not been considered first-line agents in Japan. The long-term use of unnecessary tocolysis should be avoided, and the introduction of other tocolytic drugs, including nifedipine or atosiban, should be discussed.

Currently, there are a lack of FDA-approved tocolytics for the management of preterm labor. We previously observed that the isoflavones mundulone and mundulone acetate (MA) inhibit intracellular Ca2+-regulated myometrial contractility. Here, we further probed the potential of these natural products to be small molecule leads for discovery of novel tocolytics by: (1) examining uterine-selectivity by comparing concentration-response between human primary myometrial cells and a major off-target site, aortic vascular smooth muscle cells (VSMCs), (2) identifying synergistic combinations with current clinical tocolytics to increase efficacy or and reduce off-target side effects, (3) determining cytotoxic effects and (4) investigating the efficacy, potency and tissue-selectivity between myometrial contractility and constriction of fetal ductus arteriosus (DA), a major off-target of current tocolytics. Mundulone displayed significantly greater efficacy (Emax = 80.5% vs. 44.5%, p=0.0005) and potency (IC50 = 27 M and 14 M, p=0.007) compared to MA in the inhibition of intracellular-Ca2+ from myometrial cells. MA showed greater uterine-selectivity, compared to mundulone, based on greater differences in the IC50 (4.3 vs. 2.3 fold) and Emax (70% vs. 0%) between myometrial cells compared to aorta VSMCs. Moreover, MA demonstrated a favorable in vitro therapeutic index of 8.8, compared to TI = 0.8 of mundulone, due to its significantly (p

Background:Preterm birth is the major cause of perinatal mortality and morbidity worldwide. Attempts to reduce the burden may be proactive using biochemical or biophysical prediction and preventative measures. If these efforts fail, then the approach may have to be reactive using tocolytics to inhibit spontaneous preterm labour.Objective:We have reviewed the evidence concerning the safety and efficacy of various classes of tocolytic agents.Results:The evidence to support the use of magnesium sulfate or nitric oxide donors as a tocolytic is poor. Compared to placebo or no treatment, there is evidence to support the efficacy of calcium channel blockers (mainly nifedipine), prostaglandin synthetase inhibitors (mainly indomethacin and sulindac), oxytocin receptor antagonists (mainly atosiban) and β2-agonists (mainly ritodrine, terbutaline, salbutamol and fenoterol). Maternal safety concerns have reduced the use of β2-agonists. Fetal safety and gestational age restrictions have largely condemned prostaglandin synthetase inhibitors to second-line therapy. First-line therapy in Europe and other parts of the world outside the USA and Australia is limited to calcium channel blockers and oxytocin receptor antagonists. With respect to efficacy, atosiban and nifedipine are similar, but the robustness of the evidence favours atosiban. With respect to safety, atosiban is clearly the safest tocolytic as there are fetomaternal concerns with nifedipine, particularly in high daily doses.Conclusion:The perfect tocolytic that is uniformly effective and safe does not exist. Cost, licensing and informed consent are considerations involved in the choice. Efforts continue to develop and introduce other or better agents, including novel compounds such as progesterone, PGF2α antagonists and statins.

AIMS: To investigate presence or absence of clinically relevant drug interactions (pharmacokinetic and safety/tolerability) of OBE022 with standard‐of‐care medicines for preterm labour, enabling coadministration and further clinical development. METHODS: Part A: open‐label, randomized, 3‐period crossover assessing coadministration of single doses of OBE022 (1100 mg) and MgSO(4). Part B: open‐label, single‐sequence crossover assessing the interactions following administration of OBE022 (1000 mg/day) at steady state coadministered with single doses of atosiban, nifedipine and betamethasone. Twenty‐five healthy nonpregnant women of reproductive age were enrolled (Part A: n = 12; Part B: n = 13). RESULTS: OBE022, alone or in combination with standard‐of‐care medications, was well tolerated. Headache and dizziness were the most frequently reported adverse events; dizziness occurred more often with the nifedipine/OBE022 combination. There were no clinically significant pharmacokinetic interactions when coadministered with MgSO(4). Co‐administration had no notable effect on atosiban exposure. Atosiban reduced exposure to OBE002 (peak concentration [C(max)] 22%, area under the concentration–time curve [AUC] 19%). Coadministration with betamethasone slightly increased betamethasone exposure (C(max) + 18%, AUC +27%) and OBE002 exposure (C(max) + 35%, AUC +15%). These changes were not considered clinically significant. Coadministration with nifedipine slightly increased OBE002 exposure (C(max) + 29%, AUC +24%) and markedly increased nifedipine exposure (C(max) by 2‐fold and AUC by 2‐fold), which may be clinically significant. CONCLUSIONS: The use of OBE022, a PGF2α antagonist prodrug, in combination with standard‐of‐care medicines may provide new treatment alternatives for preterm labour. All tested combinations were well tolerated. Nifedipine doses could potentially be reduced or staggered when coadministered with OBE022.

Background Two tocolytic drugs-atosiban and nifedipine-are currently used for first-line treatment of preterm labor (PTL). Objective To compare the efficacy and safety of atosiban with nifedipine for PTL treatment. Search strategy In May 2017, we searched PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Clinical Trials with search terms including "nifedipine", "atosiban", and "preterm labor". Selection criteria Randomized controlled trials of women with PTL. Data collection and analysis Data were extracted for study design, patient characteristics, risk of bias domains, and study outcomes. A random-effects model was used to generate pooled risk ratios (RRs) and 95% confidence intervals (CIs). Results We included seven studies that enrolled 992 patients. There was no significant difference between atosiban and nifedipine for pregnancy prolongation of 48 hours or more regarding efficacy (RR 1.06, 95% CI 0.92-1.22; P=0.440) or effectiveness (0.93, 0.84-1.03; P=0.177). Pregnancy prolongation for 7 days or more also did not differ between groups for efficacy (RR 1.04, 95% CI 0.89-1.21; P=0.656) or effectiveness (0.91, 0.79-1.05; P=0.177). Atosiban-however-was associated with fewer maternal side-effects than nifedipine. Conclusion Atosiban resulted in fewer maternal side-effects than nifedipine, with no difference in pregnancy prolongation. PROSPERO registration: CRD42018090223.

Introduction Targeted intervention to the uterus has great potential for the treatment of obstetric complications (eg, preterm birth, dysfunctional labor, and postpartum hemorrhage) by improving the effectiveness and safety of therapeutic compounds. In particular, targeting the oxytocin receptor (OTR) is a novel approach for drug delivery to the uterus. The aim of this study was to report the complete data set for the pharmaceutical synthesis and in vitro characterization of PEGylated liposomes conjugated with anti-OTR monoclonal antibodies (OTR-Lipo) or atosiban (ATO-Lipo, OTR antagonist). Methods OTR-targeted liposomal platforms composed of 1,2-distearoyl-sn-glycero-2-phosphocholine and cholesterol were prepared according to the method of dried lipid film hydration. Ligands were conjugated with the surface of liposomes using optimized methods to maximize conjugation efficiency. The liposomes were characterized for particle size, ligand conjugation, drug encapsulation, liposome stability, specificity of binding, cellular internalization, mechanistic pathway of cellular uptake, and cellular toxicity. Results Both OTR-Lipo and ATO-Lipo showed significant and specific binding to OTRs in a concentration-dependent manner compared to all control groups. There was no significant difference in binding values between OTR-Lipo and ATO-Lipo across all concentrations evaluated. In addition, OTR-Lipo (81.61%±7.84%) and ATO-Lipo (85.59%±8.28%) demonstrated significantly increased cellular internalization in comparison with rabbit IgG immunoliposomes (9.14%±1.71%) and conventional liposomes (4.09%±0.78%) at 2.02 mM phospholipid concentration. Cellular association following liposome incubation at 4.05 mM resulted in similar findings. Evaluation of the mechanistic pathway of cellular uptake indicated that they undergo internalization through both clathrin- and caveolin-mediated mechanisms. Furthermore, cellular toxicity studies have shown no significant effect of both liposomal platforms on cell viability. Conclusion This study further supports OTRs as a novel pharmaceutical target for drug delivery. OTR-targeted liposomal platforms may provide an effective way to deliver existing therapies directly to myometrial tissue and avoid adverse effects by circumventing non-target tissues.

Objective To assess the cost-effectiveness of treatment with nifedipine compared with atosiban in women with threatened preterm birth. Design An economic analysis alongside a randomised clinical trial (the APOSTEL III study). Setting Obstetric departments of 12 tertiary hospitals and seven secondary hospitals in the Netherlands and Belgium. Population Women with threatened preterm birth between 25 and 34 weeks of gestation, randomised for tocolysis with either nifedipine or atosiban. Methods We performed an economic analysis from a societal perspective. We estimated costs from randomisation until discharge. Analyses for singleton and multiple pregnancies were performed separately. The robustness of our findings was evaluated in sensitivity analyses. Main outcome measures Mean costs and differences were calculated per woman treated with nifedipine or atosiban. Health outcomes were expressed as the prevalence of a composite of adverse perinatal outcomes. Results Mean costs per patients were significantly lower in the nifedipine group [singleton pregnancies: euro34,897 versus euro43,376, mean difference (MD) -euro8479 [95% confidence interval (CI) -euro14,327 to -euro2016)]; multiple pregnancies: euro90,248 versus euro102,292, MD -euro12,044 (95% CI -euro21,607 to euro -1671). There was a non-significantly higher death rate in the nifedipine group. The difference in costs was mainly driven by a lower neonatal intensive care unit admission (NICU) rate in the nifedipine group. Conclusion Treatment with nifedipine in women with threatened preterm birth results in lower costs when compared with treatment with atosiban. However, the safety of nifedipine warrants further investigation. Tweetable abstract In women with threatened preterm birth, tocolysis using nifedipine results in lower costs when compared with atosiban.

Preterm birth is defined as delivery before 37 completed weeks of pregnancy, and it is the leading cause of neonatal morbidity and mortality. Oxidative stress is recognized as an important factor in the pathogenesis of premature labor. We conducted this analysis to investigate the safety of administration of the tocolytic drug Atosiban—a reversible, competitive antagonist of the oxytocin receptor in the treatment of preterm birth and its impact on the level of oxidative stress in pregnant women after 48 hours of tocolytic treatment. This prospective study was conducted between March 2016 and August 2017 at the Obstetric Clinic of the Polish Mother’s Memorial Hospital Research Institute. Total oxidant status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI) values as well as 3-nitrotyrosine, carbonyl, and thiol group levels were measured using an ELISA test in serum and plasma of 56 pregnant women before and after 48 hours of continuous administration of Atosiban. We found that TAS levels decreased almost twice after the 48-hour drug administration (0.936 ± 0.360 mmol/L vs. 0.582 ± 0.305 mmol/L, P<0.001) while TOS increased from 18.217 ± 16.093 μmol/L to 30.442 ± 30.578 μmol/L (P<0.001). We also found a significant increase in OSI index—almost a threefold increase from 0.022 ± 0.022 to 0.075 ± 0.085, P<0.001. In addition, statistically significant differences in the level of carbonyl groups were found. It increased from 65.358 ± 31.332 μmol/L to 97.982 ± 38.047 μmol/L (P<0.001), which indicates increased oxidation of plasma proteins. Furthermore, patients who gave birth prematurely had higher levels of TOS after a 48-hour drug administration than the second group with labor after 37 weeks of pregnancy (42.803 ± 34.683 μmol/L vs. 25.792 ± 27.821 μmol/L, P<0.031). The obtained results clearly indicate that pregnant women during tocolytic treatment with Atosiban are in a state of increased oxidative stress and occurrence of preterm birth can be associated with this phenomenon. This trial is registered with NCT03570294.

Objectives To compare the effects of atosiban (oxytocin antagonist) on uterine peristalsis and pregnancy outcomes in the frozen embryo transfer (FET) cycle. Setting Srinagarind Hospital, a university hospital, Khon Kaen, Thailand. Design A randomized, double-blinded, controlled trial. Methods Fifty infertile women were randomized into the atosiban (n = 25) and placebo group (n = 25). Women in the study group received intravenous atosiban 6.75 mg, 30 min before embryo transfer, and continued infusion at 18 mg/h for 1 h. The dose was reduced to 6 mg/h for another 2 h. Saline solution was applied in the placebo group. The uterine peristalsis frequency was measured by transvaginal ultrasound 30 min before and 3 h after the embryo transfer. Results The respective mean baseline uterine peristalsis frequency (time) in the atosiban and placebo group was 10.3 ± 2.4 and 9.2 ± 3.4. The respective duration of uterine peristalsis in the atosiban and placebo group after receiving the intervention was reduced to 7.9 ± 2.1 and 6.9 ± 2.7. The implantation rate and clinical pregnancy rate were not statistically significant different between atosiban group and placebo group (37.5% versus 31.0%, RR 1.21, 95%CI: 0.60–2.44 and 44% versus 36%, RR 1.22, 95%CI: 0.62–2.42, respectively). Subgroup analysis indicated that the clinical pregnancy rate in those >35 years of age was not significantly different between both groups (31.6% and 18.8 %, RR 1.68, 95%CI: 0.50–5.68). Conclusion Adding atosiban in FET did not reduce uterine peristalsis but may benefit the advanced age group.

During the emission phase of ejaculation, the sperm is driven from the cauda epididymidis, where it is stored, through the vas deferens by strong contractions. These contractions are thought of as being mainly induced by the sympathetic nervous system and the neurotransmitter noradrenaline. In the present study, we investigated the effect of oxytocin (suggested to exert effects during ejaculation as well) on defined segments of the rat and human epididymis using live imaging. Our results indicate that it is the very last part of the epididymis, segment 19 (S19) in rat and likewise segment 9 in human, which responds in a uniquely strong and rapid manner to oxytocin (similar to noradrenaline). Because of the complex nature of this contractile response, we developed an imaging analysis method, which allowed us to quantify multidirectional contractions and to display them using heat maps. The reaction of S19 to oxytocin was concentration-dependent and could be inhibited by pretreatment with oxytocin antagonists (atosiban and cligosiban), but not with an arginine vasopressin 1A antagonist (SR49059). In both rat and human tissue, pretreatment with the alpha-1 adrenoreceptor antagonist tamsulosin inhibited the response to noradrenaline, whereas the effect of oxytocin was unimpaired. Our data (from men and rodents) strongly suggest that the hormone oxytocin is involved in the ejaculatory process. Thus, oxytocin-based medications might be a promising non-adrenergic treatment option for ejaculatory disorders. Additionally, we propose that S19 could be an advantageous model (detecting very low concentrations of oxytocin) to test the bioactivity of new oxytocin agonists and oxytocin antagonists.

BACKGROUND Premature labor is an important cause of infant death and long-term disability. This study aimed to explore the safety and effectiveness of combining the tocolytic agents atosiban and ritodrine to extend gestation. MATERIAL AND METHODS The study included 52 patients with late threatened abortion and threatened premature labor between 20⁰⸍⁷ and 33⁶⸍⁷ weeks' gestation who were administrated continuous tocolytic agents for 48 h. Patients were divided into a research group receiving ritodrine combined with atosiban, owing to having no response to ritodrine alone (n=30), and a control group receiving ritodrine alone (n=22). The mean infusion rate and duration of tocolytic administration, gestation extension, pregnancy outcomes, and adverse effects were recorded. Routine blood tests, including C-reactive protein, and cultures for leukorrhea, candida, and mycoplasma were performed before and 1 week after treatment. RESULTS Patients receiving ritodrine with atosiban had a mean gestation extension of 42.53±31.70 days. The extension of gestation of the research group was statistically shorter than that of the control group (P0.05). The fetal loss rate, newborn birth weight, and Apgar score at 1 min were similar between the 2 groups (all, P0.05). The research group had a lower incidence of palpitations than the control group (P0.05). CONCLUSIONS For patients with late threatened abortion or threatened premature labor not controlled with ritodrine alone, ritodrine combined with atosiban extends gestation and improves pregnancy outcomes. For patients with abnormal uterine contractions, routine testing for reproductive tract infection should be performed. When infection is present, anti-infective therapy should be administered.

Repeated implantation failures are a constant challenge in reproductive medicine with a significant impact both on health providers and on infertile couples. Several approaches have been proposed so far as effective; however, accumulative data have clarified that most of the treatment options do not have the evidence base for a generalized application to be suggested by the relevant societies. Implantation failures are attributed to either poor quality embryos or to defected endometrial receptivity. The current review aims to summarize in a systematic way all the new trends in managing RIF via interference with endometrial receptivity. The authors focus mainly, but not exclusively, on endometrial injury prior to embryo transfer and endometrial priming with autologous cells or biological agents. To this direction, a systematic search of the Pubmed database has been conducted taking into account the emerged evidence of the last two decades. All the suggested interventions are herein presented and analyzed in terms of reproductive outcomes. It is evident that properly powered and designed randomized trials are needed to support a new standard approach in RIF treatment that will safely be incorporated in national and international guidelines.

Bryophyllum pinnatum has been used in the treatment of premature labor, first in anthroposophic hospitals and, recently, in conventional settings as an add-on medication. In vitro work with hTERT human myometrial cells showed that B. pinnatum leaf press juice inhibits the increase of intracellular free calcium concentration induced by oxytocin, a hormone known to play a role in labor. Our aim was to identify fractions/compounds in B. pinnatum press juice that contribute to this inhibitory effect, and to investigate their effect on oxytocin-driven activation of the MAPK cascade. Several fractions/compounds from B. pinnatum press juice led to a concentration-dependent decrease of oxytocin-induced increase of intracellular free calcium concentration, but none of them was as strong as B. pinnatum press juice. However, the combination of a bufadienolide and a flavonoid-enriched fraction was as effective as B. pinnatum press juice, and their combination had a synergistic effect. B. pinnatum press juice inhibited oxytocin-driven activation of MAPKs SAPK/JNK and ERK1/2, an effect also exerted by the bufadienolide-enriched fraction. The effect of B. pinnatum press juice on oxytocin-induced signaling pathways was comparable to that of the oxytocin-receptor antagonist and tocolytic agent atosiban. Our findings further substantiate the use of B. pinnatum press juice preparations in the treatment of preterm labor.

There has been accumulating evidence of human social chemo-signaling, but the underlying mechanisms remain poorly understood. Considering the evolutionarily conserved roles of oxytocin and vasopressin in reproductive and social behaviors, we examined whether the two neuropeptides are involved in the subconscious processing of androsta-4,16,-dien-3-one and estra-1,3,5 (10),16-tetraen-3-ol, two human chemosignals that convey masculinity and femininity to the targeted recipients, respectively. Psychophysical data collected from 216 heterosexual and homosexual men across five experiments totaling 1056 testing sessions consistently showed that such chemosensory communications of masculinity and femininity were blocked by a competitive antagonist of both oxytocin and vasopressin receptors called atosiban, administered nasally. On the other hand, intranasal oxytocin, but not vasopressin, modulated the decoding of androstadienone and estratetraenol in manners that were dose-dependent, nonmonotonic, and contingent upon the recipients’ social proficiency. Taken together, these findings establish a causal link between neuroendocrine factors and subconscious chemosensory communications of sex-specific information in humans.

Restraint stress (RS) is an unavoidable stress model that triggers activation of the autonomic nervous system, endocrine activity, and behavioral changes in rodents. Furthermore, RS induces secretion of oxytocin into the bloodstream, indicating a possible physiological role in the stress response in this model. The presence of oxytocin receptors in vessels and heart favors this possible idea. However, the role of oxytocin secreted in RS and effects on the cardiovascular system are still unclear. The aim of this study was to analyze the influence of oxytocin on cardiovascular effects during RS sessions. Rats were subjected to pharmacological (blockade of either oxytocin, vasopressin, or muscarinic receptors) or surgical (hypophysectomy or sinoaortic denervation) approaches to study the functional role of oxytocin and its receptor during RS. Plasma levels of oxytocin and vasopressin were measured after RS. RS increased arterial pressure, heart rate, and plasma oxytocin content, but not vasopressin. Treatment with atosiban (a Gi biased agonist) inhibited restraint-evoked tachycardia without affecting blood pressure. However, this effect was no longer observed after sinoaortic denervation, homatropine (M2 muscarinic antagonist) treatment or hypophysectomy, indicating that parasympathetic activation mediated by oxytocin secreted to the periphery is responsible for blocking the increase in tachycardic responses observed in the atosiban-treated group. Corroborating this, L-368,899 (oxytocin antagonist) treatment showed an opposite effect to atosiban, increasing tachycardic responses to restraint. Thus, this provides evidence that oxytocin secreted to the periphery attenuates tachycardic responses evoked by restraint via increased parasympathetic activity, promoting cardioprotection by reducing the stress-evoked heart rate increase.

Introduction Breech/transverse presentation is responsible for about 30–50 % of cesarean sections in the world. Cesarean section carries a five-fold greater morbidity than vaginal delivery, deeply impacting on women’s health. External Cephalic Version (ECV) is an external manipulation used to convert a non-cephalic to a cephalic presentation. The use of tocolysis might facilitate this procedure; however, it is still controversial which drug should be considered as first choice. Objective To assess the effectiveness of tocolysis with atosiban, a competitive oxytocin receptor antagonist, in order to increase the rate of successful ECV. Study design Nine databases (including MEDLINE, CINAHL, LILACS, EMBASE, Scopus, ClinicalTrials.gov, Scielo, PROSPERO, Cochrane at CENTRAL) were searched from the inception to August 2020 using a combination of MeSH terms and keywords regarding “atosiban” and “external cephalic version”. We included trials of women with a singleton pregnancy who reached at least 36 weeks of gestation and were scheduled to ECV and tocolysis with atosiban (intervention group) compared to beta-agonists or other drugs (control group). The primary outcome was the incidence of successful ECV. Summary measures were reported as relative risk (RR) with 95 % confidence interval (CI). Data collection and analysis Four studies (1534 women) were eligible for analysis. ECV success rate was significantly lower in women randomized to atosiban (36.7 % vs 45.3 %; RR 0.78 [95 % CI 0.6 to 0.98]). Cesarean section and vaginal delivery rates did not differ between intervention and control group ((59.8 % vs 52.6 %; RR 1.17 [0.98–1.38] and (38.6 % vs 45.0 %; RR 0.83 [95 % CI 0.69–1.01] respectively). Cephalic (36.9 % vs 44.6 %; RR 0.81 [95 % CI 0.65 to 1.01], or breech/transverse presentation at labor (63.4 % vs 55.1 %; RR 1.18 [95 % CI 0.99–1.40]), APGAR score less than 7 at 5 min (1.6 % vs 2.0 %; RR 1.14 [95 % CI 0.27–4.73], NICU admissions (44.2 % vs 48.1 %; RR 0.92 [95 % CI 0.58–1.46] and Umbilical cord pH were similar in both groups. Drug-related side effects were lower in women randomized to atosiban, compared with control group (16.0 % vs 42.9 %; RR 0.38 [95 % CI 0.31 to 0.47]. Conclusion The use of atosiban for tocolysis does not improve the rate of successful ECVs when compared to beta-agonists. However, atosiban was associated with a significantly lower incidence of side effects and comparable cesarean section rates.

Effective tocolysis is essential after fetal myelomeningocele repair and is associated with the development of pulmonary edema. The increased uterine activity in the immediate postoperative period is commonly treated with magnesium sulfate. However, other tocolytic agents such as nitroglycerine, nifedipine, indomethacin, terbutaline, and atosiban (outside the US) have also been used to combat uterine contractility. The ideal tocolytic regimen which balances the risks and benefits of in-utero surgery has yet to be determined. In this case report, we describe a unique case of fetal myelomeningocele repair complicated by maternal pulmonary edema and increased uterine activity resistant to magnesium sulfate therapy.

The aim of the present systematic review and meta-analysis was to assess the effect of the different therapeutic options for repeated embryo implantation failure (RIF) on a subsequent IVF cycle outcome. Twenty-two RCTs and nineteen observational studies were included. Pooling of results showed a beneficial effect of intrauterine PBMC infusion on both CPR (RR 2.18; 95% CI 1.58–3.00; p

Objective To compare the long‐term effects of tocolysis with nifedipine or atosiban on child outcome at age 2.5–5.5 years. Design The APOSTEL III trial was a multicentre randomised controlled trial that compared tocolysis with nifedipine or atosiban in 503 women with threatened preterm birth. Neonatal outcomes did not differ between both treatment arms, except for a higher incidence of intubation in the atosiban group. Methods Parents were asked to complete four questionnaires regarding neurodevelopment, executive function, behaviour problems and general health. Main outcome measures The main long‐term outcome measure was a composite of abnormal development at the age of 2.5–5.5 years. Results Of the 426 women eligible for follow‐up, 196 (46%) parents returned the questionnaires for 115 children in the nifedipine group and 110 children in the atosiban group. Abnormal development occurred in 32 children (30%) in the nifedipine group and in 38 children (38%) in the atosiban group (OR 0.74, 95% CI 0.41–1.34). The separate outcomes for neurodevelopment, executive function, behaviour, and general health showed no significant differences between the groups. Sensitivity analysis for all children of the APOSTEL III trial, including a comparison of deceased children, resulted in a higher rate of healthy survival in the nifedipine group (64 versus 54%), but there was no significant difference in the overall mortality rate (5.4 versus 2.7%). There were no significant subgroup effects. Conclusion Outcomes on broad child neurodevelopment, executive function, behaviour and general health were comparable in both groups. Neither nifedipine nor atosiban can be considered as the preferred treatment for women with threatened preterm birth. Tweetable abstract Nifedipine‐ and atosiban‐exposed children had comparable long‐term outcomes, including neurodevelopment, executive function and behaviour., Tweetable abstract Nifedipine‐ and atosiban‐exposed children had comparable long‐term outcomes, including neurodevelopment, executive function, and behaviour.

Introduction: In women with preterm ruptured membranes and contractions, the administration of tocolysis is controversial. This study compares tocolysis with no tocolysis in women with threatened preterm birth and ruptured membranes. Objective: To compare tocolysis with no tocolysis in women with threatened preterm birth and ruptured membranes. Study design: Data from the APOSTEL III RCT was combined with data from the National Maternity Hospital, Dublin. In the APOSTEL III trial, women with threatened preterm birth were randomized to atosiban or nifedipine. Patient data from Ireland were obtained from a cohort of women with threatened preterm birth with ruptured membranes. The Irish women received no tocolytic treatment. Only women with ruptured membranes and contractions were selected. We studied women with singleton or twin pregnancies and a gestational age between 25+0 and 33+6 weeks. Propensity score matching was performed to create comparable groups. Primary outcome was a composite adverse neonatal outcome. Secondary outcomes were individual components of the primary outcome, as well as neonatal intensive care unit (NICU) admission, gestational age at delivery, prolongation of pregnancy and mode of delivery. Results: 153 women from the Apostel III trial were compared with 51 eligible women of the Irish cohort. We could match 46 women who received tocolysis and 46 women who received no tocolysis. All women had ruptured membranes. Maternal age, BMI, parity and gestational age at study entry were comparable between the groups after matching. There were no statistically significant differences in neonatal composite outcome (9.6 % in the tocolysis group versus 18 % in the control group, OR 0.46, 95 % CI 0.13−1.63). We found a lower incidence of NICU admission in the tocolysis group (63 %) than in the control group (94 %; OR 0.11, 95 % CI 0.03−0.41), which could be explained by differences in national admission policies. There were no statistically significant differences between tocolysis and no tocolysis in any of the other outcomes including sepsis, gestational age at delivery and time to delivery. Conclusion: In this propensity score analysis of women with threatened preterm birth and ruptured membranes, tocolytic therapy did not alter composite adverse neonatal outcome or time to delivery.

Key points A moderate level of exercise has beneficial effects for the prevention of gastric ulcers. Although regular aerobic exercise was shown to elevate serum oxytocin levels and exogenously administered oxytocin exerts an anti-ulcer activity, the role of endogenous oxytocin in the gastroprotective effects of exercise has not yet been elucidated. We showed that increased anxiety and oxidative gastric damage induced by gastric ulcers were reversed in pre-exercised rats, while reduced hypothalamic oxytocin expression and decreased myenteric oxytocin receptor expression due to gastric ulcers were abolished by exercise. We also reported that the blockade of oxytocin receptors exaggerated gastric damage in exercised rats with ulcers. Our data establish that endogenous oxytocin is the key mediator in the beneficial effects of regular physical activity in alleviating gastric injury. Abstract Exercise increases serum oxytocin levels and exogenous oxytocin exerts an anti-ulcer activity; but the role of oxytocin in the protective effects of exercise against gastric ulcers has not yet been evaluated. This study was designed to investigate the impact of regular swimming exercise on oxidative gastric injury, and the role of oxytocin receptor activity in the anxiolytic and anti-inflammatory actions of exercise. Adult Wistar albino rats of both sexes performed swimming exercise (30 min/day, 5 days) or stayed sedentary. At the end of the 6-week exercise/sedentary protocol, rats were injected intraperitoneally with atosiban (0.1 mg/kg/day) or saline for 4 days. On the 5th day, under anaesthesia, acetic acid (ulcer) or saline (sham) was applied onto the gastric serosa and the treatments were continued. On the 9th day, anxiety levels were determined; gastric blood flow was measured, and blood, gastric and brain tissues were obtained. Induction of ulcers in sedentary rats increased anxiety and serum corticosterone levels; but reduced gastric blood flow and resulted in apoptosis and oxidative gastric damage with increased cytokine expressions. However, when ulcers were induced in pre-exercised rats, behavioural and biochemical alterations due to gastric damage were reversed. The inhibition of oxytocin receptors by atosiban exaggerated pro-inflammatory cytokine expressions and gastric lipid peroxidation in the stomachs of exercised rats with ulcers. When rats had regularly exercised prior to ulcer induction, reductions in the immunolabelling of hypothalamic oxytocin and myenteric oxytocin receptors were abolished, suggesting that exercise-induced alleviation of gastric injury may involve the reversal of down-regulated oxytocinergic activity.

Introduction The breech presentation represents 4,7% of deliveries at term. There is a method of external cephalic version (ECV) performed from 36 weeks of gestation. French guidelines for the clinical practice of ECV were published in 2020. Objective To evaluate the national practices of ECV in French maternity units, especially on the use of tocolysis, 1 year after publication of the French clinical recommendations guidelines by the French national college of obstetricians and gynecologists (CNGOF). Methods Data self-reported for this national descriptive study were collected from March to May 2021 by an online questionnaire distributed to all French maternities. The 25 items of the questionnaire collected information of maternity units, the general practice of ECV, use or not of tocolysis for ECV attempt and the relevance of a prospective study. Results Of the 517 French maternity units, 150 (29%) responded to the online survey. 95,3% systematically performed ECV. A Kleihauer test was routinely performed in 71 units (49.7%). A tocolysis was associated with ECV attempt in 52.4% of cases. The drugs used were intravenous atosiban (30,7%), mainly in levels 2b and 3 maternity units, intravenous salbutamol (24%), other mode of administration of salbutamol (14,7%) and oral nifedipine (22,6%) mainly in levels 1 and 2a maternity units. Adverse effects were described in 20%, mainly with the use of salbutamol (73,3%). Conclusions 52.4% of the French maternity units surveyed used tocolysis for the ECV attempt, although it is systematically recommended. The choice of tocolytic drug differed according to the maternity units.

There is increasing evidence that oxytocin is involved in learning and memory process. This study investigated the effects of blockade of oxytocin receptors using the selective oxytocin receptor antagonist atosiban (ATO) on contextual fear memory consolidation and reconsolidation in male rats. Post-training injections of different doses of ATO (1, 10, 100 or 1000 µg/kg) impaired the 48 h retention performance in a dose-dependent manner. The same doses of ATO following memory reactivation did not impair subsequent expression of contextual fear memories which formed under low or high shock intensities and tested 24 h or one week following memory reactivation. Also, no effect was found when ATO was administrated in the absence of memory reactivation. Our finding is the first report that indicates endogenous oxytocin released during training play an important role in the consolidation, but not reconsolidation of contextual fear memory in rats.

Social factors have a dual influence on addictive disorders. While social defeat stress in rodents increases the response to drug reward, positive social conditions, such as pair housing, increase stress resilience. The objective of the present study was to confirm whether oxytocin (OT) mediates this social buffering. To this end, male mice were housed in pairs and administered the OT receptor antagonist atosiban prior to each stress episode or for ten days after the stress protocol. The response to cocaine was assessed using a conditioned place preference paradigm. Our results confirmed that OT activity mediates the protective effect of pair housing and highlights its therapeutic potential.