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Human brain development is a complex process that begins in the third week of gestation. During early development, the fetal brain undergoes dynamic morphological changes. These changes result from events such as neurogenesis, neuronal migration, synapse formation, axonal growth and myelination. Disruption of any of these processes is thought to be responsible for a wide array of different pathologies. Recent advances in magnetic resonance imaging, especially diffusion-weighted imaging and diffusion tensor imaging (DTI), have enabled characterization and evaluation of brain development in utero. In this review, aimed at practitioners involved in fetal medicine and high-risk pregnancies, we provide a comprehensive overview of fetal DTI studies focusing on characterization of early normal brain development as well as evaluation of brain pathology in utero. We also discuss the reliability and limitations of fetal brain DTI. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

OBJECTIVE To describe prenatal decision-making processes and birth plans in pregnancies amenable to planning perinatal palliative care. DESIGN Multicentre prospective observational study. SETTING Nine Multidisciplinary Centres for Prenatal Diagnosis of the Paris-Ile-de-France region. POPULATION All cases of major and incurable fetal anomaly eligible for TOP where limitation of life-sustaining treatments for the neonate was discussed in the prenatal period between 2015 and 2016. METHODS Cases of congenital defects amenable to perinatal palliative care were prospectively included in each centre. Prenatal diagnosis, decision-making process, type of birth plan, birth characteristics, pregnancy and neonatal outcome were collected prospectively and anonymously. MAIN OUTCOME MEASURE Final decision reached following discussions in the antenatal period. RESULTS We identified 736 continuing pregnancies with a diagnosis of a severe fetal condition eligible for TOP. Perinatal palliative care was considered in 102/736 (13.9%) pregnancies (106 infants); discussions were multidisciplinary in 99/106 (93.4%) cases. Prenatal birth plans involved life-sustaining treatment limitation and comfort care in 73/736 (9.9%) of the pregnancies. The main reason for planning palliative care at birth was short-term inevitable death in 39 cases (53.4%). In all, 76/106 (71.7%) infants were born alive, and 18/106 (17%) infants were alive at last follow-up, including four with a perinatal palliative care birth plan. CONCLUSIONS Only a small proportion of severe and incurable fetal disorders were potentially amenable to limitation of life-sustaining interventions. Perinatal palliative care may not be considered a universal alternative to termination of pregnancy. TWEETABLE ABSTRACT Perinatal palliative care is planned in 10% of continuing pregnancies with a major and incurable fetal condition eligible for TOP.

CMV DNA is detectable in the amniotic fluid collected by amniocentesis, in cases that the fetus has been infected. However, in the literature there are reported cases of congenital neonatal CMV infection with a negative amniocentesis. The aim of the present study is to compare pregnancies with negative amniocentesis to those with positives amniocentesis, in terms of fetal insult and long-term sequelae.Cohort and observational studies performing amniocentesis in mothers with congenital CMV infection and reporting their results, together with neonatal and/or long-term outcomes of the offspring were included. The risk of bias in included studies was assessed using the Newcastle-Ottawa Scale (NOS). The presence of severe symptoms at birth, defined as the presence of neurological symptoms or multiorgan involvement at birth, and (2) the presence of severe sensorineural hearing loss (SNHL), and/or neurodevelopmental impairment at follow-up were the main outcomes of the study.Seven studies were included in the meta-analysis. The pooled false negative rate of amniocentesis was 8.0% (95%CI 5.0-13.0). The pooled rate of severe symptoms at birth, in the fetuses with negative amniocentesis was 0.0% (95%CI: 0.0%-1.0%, IA negative amniocentesis in pregnant women with CMV infection ensures lack of fetal insult and long-term sequelae to the child, even if transmission has occurred. This article is protected by copyright. All rights reserved.

OBJECTIVE To identify risk factors for early- and late-onset postpartum depression (PPD) among a wide range of variables, including sociodemographic characteristics, childhood trauma, stressful life events during pregnancy and history of personal and family psychiatric disorders, and to assess the contribution of each risk factor. DESIGN Nested case-control study in a prospective longitudinal cohort study. SETTING Eight maternity departments in the Paris metropolitan area, France. SAMPLE A cohort of 3310 women with deliveries between November 2011 and June 2016. METHODS Cases were women with early- or late-onset PPD. Controls were women without depression during pregnancy or the postpartum period. Logistic regression adjusted on sociodemographic variables was performed for each outcome and a multivariable model was proposed based on a stepwise selection procedure. MAIN OUTCOME MEASURES Early- and late-onset PPD assessed at 2 months and 1 year postpartum, respectively. RESULTS Stressful life events during pregnancy have a dose-response relationship with both early- and late-onset PPD. CONCLUSIONS Early- and late-onset PPD presented distinct patterns of determinants. These results have important consequences in terms of prevention and specific care. TWEETABLE ABSTRACT Early- and late-onset postpartum depression are associated with stressful life events and psychiatric history.

Analyze the complication rate of pregnancy termination between 12 and 16 weeks of gestation, depending on the method and the exact term.Retrospective study focuses on patients who were going through a pregnancy termination between January 2015 and December 2020 at the Necker Universitary hospital in Paris. Two methods were applied: surgical abortion or medical evacuation. We compared 4 groups of patients depending on methods and term (12-14 or 14-16 weeks of gestation). The main complications such as hemorrhage, infection, need for surgery were collected.414 patients were included. Blood loss and hemorrhage rate500cc were higher for surgical abortion (3.5 vs 55% P0.001), but the medical evacuation lead to an important rate of secondary aspiration for trophoblastic retention (14.7% vs 1.5% P0.001). We didn't observe any difference regarding the complication rate for medical evacuation depending on the term. However, in case of surgical abortion the increase of term from 12-14 to 14-16 weeks of gestation leads to a tiny increment of the transfusion rate (0.6% vs 4.4% P=0.04), even if the hemorrhage rate500cc didn't significantly differ (50,3 vs 57,9% P=0,2).Surgical abortion between 12 and 16 weeks of gestation exposed the patients to an increased hemorrhagic risk, while the medical evacuation required more secondary aspiration for trophoblastic retention. The term of the abortion didn't affect the complication rate, beside a tiny increase in transfusion rate for surgical abortion.

To identify favorable renal histology in fetuses with early severe lower urinary tract obstruction (LUTO) and determine the best timing and selection criteria for prenatal surgery.This multicenter, retrospective study included male fetuses with severe LUTO which died before 24 weeks of gestation during the period January 2000 to December 2018. Age-matched controls were used as reference standard for renal histology. Prenatal ultrasound features and fetal serum and/or urine β2microglobulin level were retrieved and kidney histology slides (hematein-eosin-safran and α-smooth-muscle-actin (αSMA) immunostaining) were prepared and reviewed. αSMA-positive staining of the blastema is due to its aberrant differentiation into myofibroblastic cells. Cases were sorted into histopathologic groups (favorable or unfavorable) according to the blastema's morphology and αSMA labeling and the data of these groups were compared.Included in the study were 74 fetuses with a median gestational age at outcome of 17 + 6 (range, 13 + 0 to 23 + 5) weeks. Parenchymal organization was preserved in 48% of the kidneys. A blastema was present in 90% of the kidneys, but it was morphologically normal in only 9% and αSMA-negative in only 1% of them. Most (82%) fetuses had an unfavorable prognosis, and 36% of fetuses died ≤ 18 weeks and had severe renal lesions detected on histology (early unfavorable prognosis). A favorable renal prognosis was associated with an earlier gestational age (P = 0.001). Fetuses with LUTO had a significantly lower number of mature glomeruli (P 0.001) compared with controls. However, there was no significant difference in the number of glomeruli generations between the early-unfavorable-prognosis group (≤ 18 weeks) and the group with a favorable prognosis (P = 0.19). A comparison of prenatal ultrasound features and biochemical markers between groups could not identify any prenatal selection criteria.Before 18 weeks, around 30% of fetuses with severe LUTO still have potential for kidney development. Identification of these cases would enable them to be targeted for prenatal therapy. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Fetal therapy is part of the available care offer for several severe malformations. The place of these emergent prenatal interventions in the prenatal path of care is poorly known. The objective of this study is to describe the decision-making process of patients facing the option of an emergent in utero intervention.We have conducted a retrospective monocentric descriptive study in the department of maternal-fetal medicine of Necker Hospital. We collected data regarding eligibility or not for fetal surgery and the pregnancy outcomes of patients referred for myelomeningocele, diaphragmatic hernia, aortic stenosis and low obstructive uropathies.All indications combined, 70% of patients opted for fetal surgery. This rate was lower in the case of myelomeningocele with 21% consent, than in the other pathologies: 69% for diaphragmatic hernias, 90% for aortic stenoses and 76% for uropathy. When fetal intervention was declined, the vast majority of patients opted for termination of pregnancy: 86%. In 14% of the considering fetal surgery, the patient was referred too far.The acceptance rate for fetal surgeries depends on condition. It offers an additional option and is an alternative for couples for which termination of pregnancy (TOP) is not an option. Timely referral to an expert center allows to discuss the place of a fetal intervention and not to deprive couples of this possibility.

Infection during pregnancy is common and the developing fetal brain is vulnerable to vertical transmission due to immaturity of the fetal immune system. Infection is a major cause of multiple organ abnormalities, including the neuraxis, due to the neurotropism of the infectious agents. This review sets out to give an overview of fetal infection, review the general principles of the nature and timing of the infectious insult with respect to outcomes, review the neuroimaging of infection by ultrasound and magnetic resonance imaging (MRI), and review the various pathogens involved, including the two most common, cytomegalovirus (CMV) and Toxoplasma, and also other common viral and nonviral infections.

To investigate prenatal diagnosis characteristics and pregnancy outcomes associated with isolated right aortic arch (RAA).A retrospective study including fetuses with isolated RAA, managed between January 2010 and February 2018. Cases were identified from the ultrasound databases of the expert pediatric cardiologists, who made the aforementioned diagnosis. All fetuses were examined by a fetal medicine imaging expert to exclude any extracardiac abnormality. A systematic review was performed to assess the prenatal diagnosis and outcomes of fetuses with isolated RAA.Fifty-six fetuses were diagnosed with an isolated RAA. An isolated double aortic arch (DAA) was diagnosed in one fetus. Mean gestational age at diagnosis was 24 weeks. The sex ratio (boy/girl) was 0.89. No significant abnormality was detected in invasive tests (karyotype and FISH or microarray). Only one fetus was misdiagnosed with isolated RAA. He was the only symptomatic (stridor) newborn baby and was later diagnosed with DAA. Four studies were included in our systematic review representing 115 cases of isolated RAA. One significant chromosomal abnormality was detected: a 22q11 deletion in a newborn baby who had a postnatal finding of a soft palate cleft. There was one major obstetric complication: an intrauterine fetal demise at 41 gestational weeks.Diagnosis of isolated RAA can be challenging. Invasive tests are to be discussed. The diagnosis of isolated RAA should not change obstetric monitoring. Nevertheless, an echocardiography should be performed systematically in these new newborn babies within their first month of life.

During their studies, French midwives need to acquire basic ultrasound skills to measure the amniotic fluid index, fetal biometry and identify fetal lie and placental positions. They have a clinical ultrasound training during their curriculum to acquire these skills. Assess the contribution that a training on an obstetrical ultrasound simulator (OUS) could make to the competence of midwives and to evaluate the best time to integrate it into their curriculum.Forty students in their 4th and final year in midwifery were randomized into 2 groups. Group A learned with the traditional academic course, with a clinical ultrasound training which was followed by an evaluation on an OUS (E1A). Group B was evaluated on a simulator before the clinical ultrasound training (E1B). After these initial assessments, both groups were provided with learning and training sessions on OUS, and re-evaluated in the same exercise (E2A and E2B). Group B then completed its clinical ultrasound training and was evaluated one month later on the simulator (E3B). The evaluation consisted of scoring the biometry images according to previously published quality criteria, and of assessing their competence based on a published objective and structured assessment score of ultrasound skills (OSAUS).Evaluation 1 found comparable OSAUS scores (2.375/5 vs. 2.24/5 P=0.52) between the two groups (E1A vs. E1B) but a significantly higher image quality score for Group A (P=0.02). In Evaluation 2, an improvement was noted for both groups with comparable OSAUS averages between the two groups (P=0.76). After the clinical training of Group B, their OSAUS score (E3B) was significantly better than that of Group A (E1A) after their clinical training (3.45/5 vs. 2.375/5 [P=0.00017]). The same was true for the quality of their images (12.67/16 vs. 9.95/16 [P=0.003]).Ultrasound simulation-based training, as an adjunct to ultrasound clinical training, significantly improves obstetrical ultrasound skills. The best time to train on simulators seems to be prior to clinical training on real patients.

Objective: Vein of Galen aneurysmal malformation (VGAM) is a rare fetal anomaly, the neurological outcome of which can be good with appropriate perinatal management. However, most fetal series are too small to allow reliable statistical assessment of potential prognostic indicators. Our aim was to assess, in a two-center series of 49 cases, the prognostic value of several prenatal variables, in order to identify possible prenatal indicators of poor outcome, in terms of mortality and cerebral disability. Methods: This was a retrospective study involving 49 cases of VGAM diagnosed prenatally and managed at two centers over a 17-year period (1999–2015). All cases had undergone detailed prenatal cerebral and cardiac assessment by grayscale ultrasound, color and pulsed-wave Doppler and magnetic resonance imaging (MRI). Ultrasound and MRI examination reports and images were reviewed and outcome information was obtained from medical reports. Volume of the VGAM (on ultrasound and MRI) was calculated and development of straight-sinus dilatation, ventriculomegaly and other major brain abnormalities was noted. Cardiothoracic ratio, tricuspid regurgitation and reversed blood flow across the aortic isthmus were evaluated on fetal echocardiography. Major brain lesions were considered by definition to be associated with poor outcome in all cases. Pregnancy and fetoneonatal outcome were known in all cases. Fetoneonatal outcome and brain damage were considered as dependent variables in the statistical evaluation. Poor outcome was defined as death, late termination of pregnancy due to association with related severe brain anomalies or severe neurological impairment. Results: At a mean follow-up time of 20 (range, 0–72) months, 36.7% of the whole series and 52.9% of the cases which did not undergo late termination were alive and free of adverse sequelae. Five (10.2%) cases showed progression of the lesion between diagnosis and delivery. On univariate analysis, dilatation of the straight sinus, VGAM volume ≥ 20 000 mm3 and tricuspid regurgitation were all significantly related to poor outcome. However, on logistic regression analysis, the only variables associated significantly with poor outcome were tricuspid regurgitation and, to a lesser extent, VGAM volume ≥ 20 000 mm3. The former was also the only variable associated with brain damage. Conclusions: Major brain lesions, tricuspid regurgitation and, to a lesser extent, VGAM volume ≥ 20 000 mm3 are the only prenatal variables associated with poor outcome in fetal VGAM. Prenatal multidisciplinary counseling should be based on these variables. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Cet article a pour objectif de connaitre le devenir de 28 singletons et de leurs familles, six ans apres le diagnostic antenatal d’un syndrome transfuseur-transfuse. La recherche comprenait un entretien clinique avec les parents et un bilan psychologique avec les enfants. Les resultats au WISC IV indiquent que 78 % des enfants ont un quotient intellectuel (QI) total dans la moyenne. Pour le test du dessin du bonhomme, 64 % des enfants ont des resultats en dessous de leur classe d’âge. L’analyse du CAT revele majoritairement une inhibition de la pensee. L’analyse du contenu des entretiens a montre que la place qu’occupe le jumeau decede pour le jumeau vivant est inseparable de l’elaboration du deuil des parents.

Journal de Gynecologie Obstetrique et Biologie de la Reproduction - Vol. 38 - N° 1 - p. 5-8

The incidence of twins has dramatically increased in the last two decades. The theorical risk of aneuploidy is higher than in singletons. Screening for aneuploidies should be offered in all twin pregnancies. This review examines the current methods and evidence regarding screening for fetal aneuploidies in twin pregnancies.

To evaluate the results of screening for trisomy 21 by the combined risk of first trimester (as defined by the decree of June 23, 2009) in the Prima facie structure.Single center study involving all patients that were seen for first trimester screening at Prima facie with singleton living pregnancy, not obtained by embryo donation, between 1 January 2009 and 31 December 2014.Eighteen thousand two hundred and fifty-one patients were included, of which underwent screening for trisomy 21 by the combined risk. One thousand and forty-six (6.1%) had a calculated risk higher than 1/250. Seventy-five were affected by trisomy 21, of whom 65 in the high risk group. The sensitivity and specificity of screening are 86.7% and 94.4%. The median nuchal translucency was 0.98 MoM.Screening for trisomy 21 by calculating the combined risk of first trimester enabled to detect 86.7% of trisomy 21 with a false positive rate of 5.6%.

The aim of this study was to evaluate the obstetrical ultrasound simulator as an initiation tool for teaching obstetrical ultrasound scanning for beginners.Twenty medical students with no experience in ultrasound scan (US) received a basic theoretical ultrasonography course on US principles and 2nd trimester biometrical measurements. The participants were then divided into 2 groups (A, B). Only group A received a practical 2nd trimester scan training session on the simulator where they were asked to determine fetal and placental position, and to take the 3 biometrical standardized measurements. Group B had the same training session but with a real ultrasound machine and a pregnant volunteer. The 2 groups were then asked to perform an US session on real patients (22 weeks) during which they had to do the same US study. The time needed to complete the whole scan was analyzed. The quality of the measurements was compared based on the previously published Objective Quality Criteria scoring.The mean total score was significantly (P=0.001) better for group A (14.3±1.4) compared to group B 10.3 (±2.75) for group A and B respectively. The time needed to accomplish the whole exam tended to be longer for group A (569±174s) compared to group A (479±104s) (P=0.18).The simulator might be a useful initiation tool to obstetric ultrasound for those who never practiced. It might prove a time sparing procedure in the training process and allow trainees to reach a basic practice level before performing examinations on actual patients.

Suprasellar arachnoid cysts (SAC) in children are considered rare, but the incidence is increasing due to the improvement of prenatal diagnosis. We present 15 cases of SAC diagnosed during the antenatal period between 2005 and 2015. The records were reviewed retrospectively by specifying the radiological characteristics, treatment modalities, outcomes, and long-term monitoring. Mean follow-up was 71 months. The forms (SAC-1) accounted for 2 cases (13%) with hydrocephalus. We observed 8 (53%) lower forms (SAC-2) with interpeduncular cistern expansion without hydrocephalus. The 5 (33.5%) remaining patients showed asymmetrical forms (SAC-3). Six patients (40%) were treated by ventriculo-cysto-cisternostomy, 1 by fetoscopy, 1 (6.5%) by ventriculo-peritoneal shunt, 2 (13.5%) by pterional craniotomy, and 6 (40%) were simply followed. The surgical outcomes were initially favorable in 9 cases (100%), 1 patient (13%) had to be re-treated later. Non-operated patients were all type 2 and showed no radiological changes. In the long-term, 1 patient (6.5%) had endocrine disruption, 1 had delayed development, 2 (13.5%) had minor neuropsychological impairments, and 1 had epilepsy. Combined monitoring with prenatal MRI and ultrasound can be used to distinguish three subtypes of SAC. SAC-1 and SAC-3 have an excellent prognosis after treatment in the perinatal period. SAC-2 can benefit from simple monitoring and remain asymptomatic in their majority. This classification allows a better prognosis estimation and better treatment decision.

Los fetos procedentes de embarazos gemelares monocoriales estan expuestos a un riesgo elevado de desarrollar complicaciones inespecificas (retraso del crecimiento intrauterino, muerte fetal in utero y prematuridad) y especificas de este tipo de placentacion. El sindrome de transfusion fetofetal (STFF) complica hasta el 15% de estos embarazos con la transfusion de uno de los gemelos (receptor) a partir de su cogemelo (donante) a traves de las anastomosis vasculares placentarias. El diagnostico de STFF se basa en un conjunto de argumentos ecograficos. El tratamiento de esta complicacion se encuentra condicionado por la edad gestacional de ocurrencia y por la tolerabilidad hemodinamica de los dos fetos. La coagulacion con laser de las anastomosis placentarias es la mejor manera de tratar las formas graves y precoces (

Rapid and constant progress in prenatal diagnosis has made screening and diagnosis for fetal aneuploidy available in the first and early second trimester. However, relatively late diagnosis of severe fetal conditions has also increased due to better performance of routine second trimester ultrasound examination together with a systematic approach to fetal evaluation and determination of prognostic factors with increasing gestation. Such situations include fetal infections, brain abnormalities, and several osteochondrodysplasias. Prognostic uncertainty is often weighed against ethical and legal issues in the decision making process, leading to either early termination of a potentially normal fetus or a late termination of a fetus more severely affected with better definition of overall prognosis. Our aim is to review the current literature with regard to technique and potential complications of late terminations of pregnancy.

Due to the development of many quality control systems in the industry, increasing demands for limited health care resources and rise of legal aspects in ultrasound practice, the need for quality has also emerged in the prenatal ultrasound field. Based on the literature, various approaches for quality control based on fetal detection rates, analysis of nuchal translucency measurements or biometric measurements are reviewed. Particular emphasis is put on the use of fetal biometry to develop quality control systems based on both a qualitative or a quantitative approach.

To describe the timing of the ultrasound appearance of olfactory sulci in normal fetuses, according to gestational age.Olfactory sulci were assessed prospectively in the coronal plane on routine brain ultrasound examination in 100 normal fetuses between 22 and 31 + 6 weeks' gestation. Examinations were divided into five groups according to gestational age: Group 1, 22 to 23 + 6 weeks (n = 22); Group 2, 24 to 25 + 6 weeks (n = 9); Group 3, 26 to 27 + 6 weeks (n = 25); Group 4, 28 to 29 + 6 weeks (n = 22) and Group 5, 30 to 31 + 6 weeks (n = 22). For each fetus, olfactory sulci were assessed as absent, developing or formed.Developing sulci appeared as primitive smooth depressions in the frontal lobe, which evolved into deep sharp complete sulci in later pregnancy. It was possible to assess the development of sulci in all cases. Olfactory sulci were consistently absent in Group 1. In Group 2, 44.4% of fetuses had absent olfactory sulci and 55.6% had developing sulci. In Group 3, the olfactory sulci were still developing in 21 (84.0%) fetuses and were completely formed in four (16.0%). Sulci were completely formed in all fetuses in Groups 4 and 5.Fetal brain ultrasound can visualize developing olfactory sulci from as early as 24 weeks' gestation. After 26 weeks, fetuses have detectable olfactory sulci and, after 28 weeks, they are completely formed. Abnormal development of olfactory sulci is a key feature of CHARGE syndrome. These results may help to improve the prenatal diagnosis of CHARGE syndrome. Copyright © 2015 ISUOG. Published by John WileySons Ltd.

To review prevalence, management and prognostic factors of pulmonary stenosis (PS) in monochorionic diamniotic (MCDA) pregnancies complicated by twin-to-twin transfusion syndrome (TTTS).Retrospective study over the last 10 years in a single referral center. We reviewed fetal echocardiography data of all MC twin cases with diagnosis of isolated PS. We assessed fetoscopy characteristics of those that underwent laser coagulation. We collected data regarding perinatal outcome, neonatal echocardiography and cardiac management.We found 24 cases of isolated PS among 2091 MCDA pregnancies. Among 1052 complicated MCDA that underwent fetal laser surgery, 22 (2.09%) developed PS of which 20 were diagnosed prenatally. Two cases were diagnosed in uncomplicated MCDA pregnancies (0.2%). Four of 22 (18.18%) cases with TTTS showed in utero regression after laser treatment. Thirteen newborns (65%) required valvular dilatation. Peak systolic velocities in the pulmonary artery trunk (PSV-PA) at diagnosis and the interval between the diagnosis of TTTS and that of PS were significantly different (p 0.001 and p = 0.05 respectively) between PS requiring cardiac intervention and those who did not.An elevated PSV-PA at the time of PS diagnosis and a short time-interval between fetoscopic laser surgery and PS diagnosis are predictive of the need for interventional treatment after birth.

BACKGROUND In the management of high risk pregnancies, blood flow measurements in the umbilical arteries (Aa. umb) have reduced perinatal morbidity and mortality. No consensus has been reached about the optimal location of measurements along the umbilical cord. The present study analyses the blood flow in both umbilical arteries where they pass by the fetal bladder. PATIENTS AND METHODS In 48 normal pregnancies, Doppler examinations were used to measure the pulsatility indices (PI). From the 20th week of pregnancy onward, the PI were measured once every four weeks in the intraabdominal segments of the right and the left Aa. umb. lateral to the fetal bladder. Measurements were also done in a free loop and at the placental insertion. RESULTS For all locations, normal ranges were calculated. The PI at all four sites decreased as the pregnancies were approaching term. In the III. trimester, the standard deviations of PI were smaller than in the II. trimester. The PI at the intraabdominal segment of the right and the left umbilical arteries turned out to be similar to each other and exceeded the values measured at the free loop and at the placental insertion respectively. CONCLUSION The intraabdominal segments of the umbilical arteries were defined as a new location for PI measurements. When adopting a fixed place of measurement, it is likely that the reproducibility of PI measurements will be increased. DISCUSSION The higher PI at the intraabdominal segment of the umbilical arteries are caused by the more central location compared to the placental insertion.