Search

This study aimed to develop an early pregnancy risk scoring model for pregnancy-associated hypertension (PAH) based on maternal pre-pregnancy characteristics, such as mean arterial pressure (MAP), pregnancy-associated plasma protein-A (PAPP-A) or neither. The perinatal databases of seven hospitals from January 2009 to December 2020 were randomly divided into a training set and a test set at a ratio of 70:30. The data of a total pregnant restricted population (women not taking aspirin during pregnancy) were analyzed separately. Three models (model 1, pre-pregnancy factors only; model 2, adding MAP; model 3, adding MAP and PAPP-A) and the American College of Obstetricians and Gynecologists (ACOG) risk factors model were compared. A total of 2840 (8.11%) and 1550 (3.3%) women subsequently developed PAH and preterm PAH, respectively. Performances of models 2 and 3 with areas under the curve (AUC) over 0.82 in both total population and restricted population were superior to those of model 1 (with AUCs of 0.75 and 0.748, respectively) and the ACOG risk model (with AUCs of 0.66 and 0.66) for predicting PAH and preterm PAH. The final scoring system with model 2 for predicting PAH and preterm PAH showed moderate to good performance (AUCs of 0.78 and 0.79, respectively) in the test set. "A risk scoring model for PAH and preterm PAH with pre-pregnancy factors and MAP showed moderate to high performances. Further prospective studies for validating this scoring model with biomarkers and uterine artery Doppler or without them might be required". [ABSTRACT FROM AUTHOR]

This study was a multicenter retrospective cohort study of term nulliparous women who underwent labor, and was conducted to develop an automated machine learning model for prediction of emergent cesarean section (CS) before onset of labor. Nine machine learning methods of logistic regression, random forest, Support Vector Machine (SVM), gradient boosting, extreme gradient boosting (XGBoost), light gradient boosting machine (LGBM), k-nearest neighbors (KNN), Voting, and Stacking were applied and compared for prediction of emergent CS during active labor. External validation was performed using a nationwide multicenter dataset for Korean fetal growth. A total of 6549 term nulliparous women was included in the analysis, and the emergent CS rate was 16.1%. The C-statistics values for KNN, Voting, XGBoost, Stacking, gradient boosting, random forest, LGBM, logistic regression, and SVM were 0.6, 0.69, 0.64, 0.59, 0.66, 0.68, 0.68, 0.7, and 0.69, respectively. The logistic regression model showed the best predictive performance with an accuracy of 0.78. The machine learning model identified nine significant variables of maternal age, height, weight at pre-pregnancy, pregnancy-associated hypertension, gestational age, and fetal sonographic findings. The C-statistic value for the logistic regression machine learning model in the external validation set (1391 term nulliparous women) was 0.69, with an overall accuracy of 0.68, a specificity of 0.83, and a sensitivity of 0.41. Machine learning algorithms with clinical and sonographic parameters at near term could be useful tools to predict individual risk of emergent CS during active labor in nulliparous women. [ABSTRACT FROM AUTHOR]

Aim: To evaluate whether three‐dimensional (3D) placental vascular indices and volumes during the first trimester of pregnancy can be used as predictors of subsequent adverse outcomes. Methods: This was a prospective cohort study including women with singleton pregnancies between 10 and 13 weeks. 3D placental volume and vascular indices and uterine artery pulsatility index (UtA‐PI) were measured. Adverse outcomes were defined whether there was any of the following complications: small for gestational age pregnancy, preterm delivery, and preeclampsia. The serum pregnancy‐associated plasma protein‐A (PAPP‐A) and free beta‐human chorionic gonadotropin (β‐hCG) levels were also compared. We analyzed the screening performances of these parameters for prediction of any of adverse outcomes. Results: Of 348 women screened, 300 women were completed follow‐up. Overall, 57 (19.0%) of 300 women developed any of adverse pregnancy outcomes. Multiple logistic regression analysis demonstrated that gestational age—adjusted z‐scores of log10 placental volume (odds ratio [OR], 0.572; 95% confidence interval [CI], 0.416–0.788), log10 placental vascularization flow index (VFI; OR, 0.676; 95% CI, 0.496–0.921), and log10 UtA‐PI (OR, 1.910; 95% CI, 1.335–2.731) were significantly associated adverse pregnancy outcomes. The multivariate model combining placental VFI, placental volume, UtA‐PI, and underweight or obese body mass index exhibited the highest screening performances (AUC = 0.77) and PAPP‐A and β‐hCG did not add any significance to multivariate model. Conclusions: Placental volume and vascular indices at 10–13 weeks of gestation are significantly associated with adverse pregnancy outcomes. Combination of these placental indices and UtA‐PI could improve the screening performance for adverse outcomes. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to investigate the independent influence of maternal age on the risk of emergency cesarean section (CS) due to nonreassuring fetal heart rate or arrest disorder. Methods: This was a cross-sectional study on women with nulliparous pregnancies, who are attempting vaginal delivery at term and have a cephalic presentation without the indication of elective CS at the onset of labor. The primary outcome was the rate of emergency CS. Independent risk factors were elucidated using multivariate logistic regression analysis. Results: Of 3513 women, 541 (15.4%) delivered by emergency CS during a trial of vaginal delivery, with theses being due to nonreassuring fetal heart rate (N = 150) or arrest disorder (N = 391). In univariate analysis, both individual CS rate due to nonreassuring fetal heart rate or arrest disorder and total emergent CS rate increased with maternal age. The risk of emergency CS was also significantly higher when labor induction was performed (odds ratio (OR) 2.489, 95% confidence interval (CI) 2.043–3.033), while fetal weight was heavier (neonatal weight ≥3.5 kg; OR 2.396, 95% CI 1.956–2.934), and maternal BMI was higher (before pregnancy ≥25 kg/m2; OR 2.751, 95% CI 1.980–3.823, at delivery ≥28 kg/m2; OR 2.375 95% CI 1.915–2.946). Multivariate stepwise regression analysis showed a statistically significant increase in the risk of total emergency CS in mothers over 35 years of age, compared to that in women less than 30 years old (35–39 years group; adjusted OR 1.805 95% CI 1.347–2.418, ≥40 years group; adjusted OR 4.659 95% CI 2.709–8.013). CS due to nonreassuring fetal heart rate increased in mothers over 40 years of age (adjusted OR 5.354, 95% CI 2.386–12.017) and CS due to arrest disorder was also increased in mothers over 30 years of age (30–34 years group; adjusted OR 1.343, 95% CI 1.010–1.785, 35–39 years group; adjusted OR 1.906, 95% CI 1.357–2.679, ≥40 years group; adjusted OR 4.663, 95% CI 2.480–8.768). Similar to the result of univariate analysis, labor induction increased the risk of emergency CS (adjusted OR 2.241, 95% CI 1.828–2.747). Conclusions: Advanced maternal age is an independent risk factor of emergency CS due to nonreassuring fetal heart rate or arrest disorder during the trial of vaginal delivery. The risk of emergency CS was also increased when labor induction was performed. Therefore, the risk of emergency CS needs to be considered, especially when the labor induction is planned, in women aged 40 or more. [ABSTRACT FROM AUTHOR]

Purpose: To examine the competing risks of stillbirth versus infant death and to evaluate the optimal time of delivery in the population of small for gestational age (SGA) and non-SGA late preterm and term fetuses. Methods: This was a retrospective national cohort study of all singleton births between 34 0/7 and 42 6/7 weeks of gestation using the Korean vital statistics (n = 2,106,159). We compared the risk of infant mortality with a composite of fetal–infant mortality risk that would occur after expectant management for one additional week and evaluated the optimal time of delivery, in SGA and non-SGA pregnancies. Results: In the total population, the risk of expectant management became significantly higher than the risk of delivery, at 39 weeks and beyond, similar with non-SGA group. In the SGA group, the risk of stillbirth was significantly greater at all GAs than for non-SGA pregnancies, and the risk of infant death was significantly increased until 38 weeks (25.8 per 10,000 live births, 95% CI 20.11–32.47), and the risk of stillbirth was significantly increased at 41 weeks (11.65 per 10,000 ongoing pregnancies, 95% CI 6.95–18.09), compared to 39 weeks (12 per 10,000 live births, 95% CI 8.98–15.64 and 5.12 per 10,000 ongoing pregnancies, 95% CI 3.84–6.66, respectively). Conclusion: In Korean women, delivery between 39 and 41 weeks minimizes fetal/infant mortality, in non-SGA pregnancies. In uncomplicated SGA pregnancies, delivery between 39 and 40 weeks can be considered to decrease risk of infant death and stillbirths. [ABSTRACT FROM AUTHOR]

Background Vitiligo is a chronic autoimmune skin disorder affecting 1% of populations worldwide. Few large-scale studies have explored adverse pregnancy outcomes in patients with vitiligo. Objective To investigate adverse pregnancy outcomes in patients with vitiligo. Methods We performed a retrospective cohort study on 4738 pregnancies of women with vitiligo and 47,380 pregnancies of age-matched controls without vitiligo using the Korean National Health Insurance Claims database from 2007 to 2016. Multivariate logistic regression models were used to evaluate the associations between vitiligo and pregnancy outcomes, including live births, spontaneous abortion, cesarean delivery, preterm delivery, gestational diabetes mellitus, stillbirth, pre-eclampsia/eclampsia, and intrauterine growth retardation. Results Patients with vitiligo exhibited a significantly lower live birth rate (odds ratio, 0.870; 95% confidence interval, 0.816-0.927) and a higher incidence of spontaneous abortion (odds ratio, 1.250; 95% confidence interval, 1.148-1.362) than the control group. Limitation The Korean National Health Insurance Claims database lacks detailed clinical information on individual patients. Conclusion Vitiligo was significantly associated with an increased risk of spontaneous abortion. Further studies are needed to determine whether systemic autoimmunity explains our finding. [ABSTRACT FROM AUTHOR]

Objective: This study was conducted to analyze recent trends of multiple birth rates (MBR) and fetal/neonatal/infant mortalities according to the number of gestations in Korea. Methods: Data from 2009 to 2015 of live births, infant deaths and stillbirths were obtained from the Korean Vital Statistics. Neonatal mortality rate (NMR), infant mortality rate (IMR), and fetal mortality rate (FMR) in singleton, twin and triplet pregnancies were analyzed according to gestational period (GP; ≤ 23, 24–27, 28–31, and 32–36 weeks). Results: From 2009 to 2015, twin and triplet birth rates increased 34.5% and 154.3%, respectively. In twin births, NMR and FMR have been decreased significantly (from 10.92 to 8.62, p = 0.034 and from 41.00 to 30.55, p< 0.001, respectively), but IMR did not show significant decrease. There was no significant change of NMR, IMR, and FMR, in triplet births. Overall, in singleton, twin, and triplet births, NMR was 1.26 ± 0.09, 10.6 ± 1.12, and 34.32 ± 11.72, respectively, and IMR was 2.38 ± 0.26, 14.52 ± 1.38, and 41.13 ± 12.2, respectively. FMRs were 12 ± 1.73, 35.99 ± 3.55, and 88.85 ± 16.55, respectively, in singleton, twin, and triplet pregnancies. In spite of decreasing trends in overall mortalities, the odds ratios of NMRs and IMRs in 2015 were approximately 9-fold and 6-fold higher, respectively, in twin births, and approximately 37-fold and 20-fold higher, respectively, in triplet births, than those in singleton births. There were no significant differences in odds ratios of NMRs and IMRs at GP 32–36 among single, twin, and triplet births, although the odds ratios of FMR at GP 32–36 in triplet gestation was significantly higher than those in singleton and twin gestation. Conclusion: Neonatal/infant mortality in multiple births is still significantly high, which is mainly related with preterm birth. Close fetal monitoring is needed to prevent fetal death in triplet pregnancies, after 32 gestational weeks. [ABSTRACT FROM AUTHOR]

Background: The 2009 Institute of Medicine (IOM) guidelines for gestational weight gain (GWG) are intended for use among women in the United States. Little data are available on whether the 2009 IOM recommendations can be applied to Asian women. This study aimed to evaluate whether the recommendations are related to adverse pregnancy outcomes in Korean pregnant women. Methods and findings: A retrospective cohort study was conducted for all singleton-pregnant women at a university hospital in Korea. After classifying the enrolled women into four Korean pre-pregnancy body mass index (BMI) categories, the risk of adverse pregnancy outcomes were analyzed for women who gained inadequate or excessive GWG based on 2009 IOM recommendations. Of 7,843 pregnancies, 64.0% of women had normal pre-pregnancy BMI and 42.7% achieved optimal GWG. Across all BMI categories, adverse pregnancies outcomes such as small for gestational age (SGA), large for gestational age (LGA), preterm birth, preeclampsia, and cesarean due to dystocia were significantly associated with GWG (all P ≤ 0.001).Women with normal BMI who gained inadequate weight were more likely to develop SGA and preterm birth and less likely to develop LGA (adjusted odds ratio (aOR) 2.21, 1.33, and 0.54, respectively). Whereas, women with normal BMI who gained excessive weight were more likely to develop LGA, preterm birth, preeclampsia, and cesarean section due to dystocia (aOR 2.10, 1.33, 1.37, and 1.37, respectively) and less likely to develop SGA (aOR 0.60). Conclusions: It is tolerable for Korean women to follow recommended GWG from the 2009 IOM guidelines to decrease adverse pregnancy outcomes. This will be helpful for antenatal care on GWG not only for Korean pregnant women, but also other Asian women who have lower BMI criteria than Caucasian women. [ABSTRACT FROM AUTHOR]

Recent evidence has revealed associations between endocrine-disrupting chemicals (EDCs) and placental insufficiency due to altered placental growth, syncytialization, and trophoblast invasion. However, no epidemiologic study has reported associations between exposure to EDCs and asymmetric fetal growth restriction (FGR) caused by placenta insufficiency. The aim of this study was to evaluate the association between EDC exposure and asymmetric FGR. This was a prospective cohort study including women admitted for delivery to the Maternal Fetal Center at Seoul St. Mary's Hospital between October 2021 and October 2022. Maternal urine and cord blood samples were collected, and the levels of bisphenol-A (BPA), monoethyl phthalates, and perfluorooctanoic acid in each specimen were analyzed. We investigated linear and non-linear associations between the levels of EDCs and fetal growth parameters, including the head circumference (HC)/abdominal circumference (AC) ratio as an asymmetric parameter. The levels of EDCs were compared between fetuses with and without asymmetric FGR. Of the EDCs, only the fetal levels of BPA showed a linear association with the HC/AC ratio after adjusting for confounding variables ( β  = 0.003, p  < 0.05). When comparing the normal growth and asymmetric FGR groups, the asymmetric FGR group showed significantly higher maternal and fetal BPA levels compared to the normal growth group (maternal urine BPA, 3.99 μg/g creatinine vs. 1.71 μg/g creatinine [ p  < 0.05]; cord blood BPA, 1.96 μg/L vs. -0.86 μg/L [ p  < 0.05]). In conclusion, fetal exposure levels of BPA show linear associations with asymmetric fetal growth patterns. High maternal and fetal exposure to BPA might be associated with asymmetric FGR., Competing Interests: MY and HWK were employed by the company Goodbeing Center Co. Ltd., Republic of Korea. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Hong, Kang, Kim, Won, Kim, Wie, Shin, Choi, Jo, Kim, Yang, Kang, Lee, Park, Park and Ko.)

Purpose: We assessed prenatal detection rates of congenital heart disease (CHD) and associations between maternal serum biomarkers and non-chromosomal CHD in singleton pregnancies., Materials and Methods: This study was conducted as a secondary analysis of data obtained during a multicenter prospective cohort study that investigated the cost-effectiveness of prenatal testing for fetal aneuploidy. We analyzed the prenatal detection rate and accuracy for CHD screening via ultrasound during the second trimester, as well as associations between serum biomarkers and CHDs, in singleton newborns without chromosomal abnormalities., Results: Among 6715 women, 142 (2.1%) newborns were born with CHDs, of which 67 (1.0%) newborns had major CHDs. The prenatal detection rate for all CHDs and major CHDs were 34.5% and 58.2%, respectively. After excluding isolated ventricular septal defects, the detection rate for critical CHDs was 85.9%. Women with low pregnancy-associated plasma protein A (PAPP-A) (<0.4 multiples of the median, MOM) face increased risks of non-chromosomal CHDs [adjusted odds ratio (aOR) 2.76; 95% confidence interval (CI) 1.36-5.13] and major CHDs (aOR 7.30; 95% CI 3.18-15.59), compared to those without CHDs. A higher inhibin A level (≥2.5 MOM; aOR 4.84; 95% CI 1.42-12.46) was associated with non-chromosomal major CHDs., Conclusion: Ultrasonography performed during the second trimester by obstetricians detected over 85% of critical CHDs. Low maternal serum PAPP-A or high inhibin-A was associated with non-chromosomal CHDs. These results may contribute to an improvement in prenatal diagnosis of CHDs., Competing Interests: The authors have no potential conflicts of interest to disclose., (© Copyright: Yonsei University College of Medicine 2022.)

Objective: To evaluate whether the degree of cervical length change was associated with successful cervical dilatation during labor induction., Materials and Methods: We conducted a secondary analysis of a prospective observational study of term singleton pregnant women who underwent labor inductions. Cases of Cesarean section due to fetal distress or maternal request during the first stage of labor were excluded. The enrolled women were categorized into two groups according to achievement of full cervical dilatation. The cervical length near induction and cervical length shortening over the last four weeks of pregnancy were compared between the two groups. A receiver operating characteristics (ROC) analysis was performed to evaluate the screening performance for failed cervical dilatation during labor induction., Results: A total of 165 women were enrolled for the final analysis; of these, 145 (87.9%) women reached the second stage of labor and 20 (12.1%) women failed to achieve full cervical dilatation. Women who failed to achieve full cervical dilatation had a significantly longer cervical length near induction and less cervical length change over previous four weeks compared with women who achieved full cervical dilatation (P = 0.018 and 0.005, respectively). Multivariate analysis showed that cervical length >29 mm (odds ratios [OR], 4.15; 95% confidence interval [CI], 1.290-13.374, P = 0.017) and cervical length shortening ≦ 6 mm (OR, 5.87; 95% CI, 1.552-22.271, P = 0.009) were significantly associated with failed cervical dilatation after adjusting for birthweight and previous history of vaginal delivery. Cervical length shortening alone provided a better prediction of failed cervical dilatation than the combination of cervical length and shortening (sensitivity, 76.9%; specificity, 63.8%)., Conclusion: The probability of failed cervical dilatation during labor induction was significantly increased in cases when the cervical length was greater than 29 mm near induction or when the cervical length shortening was less than 6 mm over the last four weeks., Competing Interests: Declaration of competing interest The researcher claims no conflict of interest., (Copyright © 2021. Published by Elsevier B.V.)

Objective: to investigate pertussis vaccination rates during pregnancy and the routine recommendation rates by maternity healthcare professionals (HCPs), including influencing factors, in Korea., Materials and Methods: Two different questionnaires were developed and conducted anonymously for pregnant or postpartum women and maternity HCPs in 30 multi-centers. Maternal pertussis vaccination rates and maternity HCPs' recommendation rates were analyzed. Independent influencing factors were analyzed using multivariate logistic regression analysis, respectively., Results: The rate of pertussis vaccination during pregnancy among 466 women was 67%. Among 164 multiparous women, 35.5% received pertussis vaccinations during every pregnancy. However, 27.9% among all pregnant women did not receive information about pertussis and vaccination. The independent influencing factors for maternal pertussis vaccination, given as the tetanus, diphtheria and acellular pertussis (Tdap), were "getting informed" (OR 18.597, 95% CI 11.206-30.861), "informed by OBGYN doctors" (OR 4.426, 95% CI 2.144-9.267), and "metropolitan residence" (OR 3.048, 95% CI 1.419-6.548). Among a total of 373 maternity HCPs, 210 (56.3%) routinely recommended pertussis vaccination, but 21.7% of the total maternity HCP participants did not know the maternal Tdap guideline. The independent factors affecting routine recommendation were the awareness of guideline (OR 9.771, 95% CI 5.227-18.265, p < 0.001) and personal pertussis vaccination within 10 years (OR 3.108, 95% CI 2.377-10.329, p < 0.001). The barriers for routine recommendation were the lack of informational materials (29%), time (25%), and knowledge (23%)., Conclusion: To increase pertussis vaccination coverage in pregnant women, more education for maternity HCPs, increase the personal pertussis vaccination rates of HCPs, and informational materials, are needed., Competing Interests: Declaration of competing interest All authors have no potential conflicts of interest., (Copyright © 2021. Published by Elsevier B.V.)

Objective: The association between abortion and postmenopausal mental health has not been clearly established in Asian women. The objective of this study was to evaluate the effect of abortion experiences on suicidal ideation and mental health in Korean postmenopausal women., Materials and Methods: This study included 5133 postmenopausal women registered in the Korean National Health and Nutrition Examination Survey between 2010 and 2012. Difference in suicidal ideation according to type and number of abortions was analyzed. We used survey multiple logistic regression analysis to evaluate the effect of abortion experiences on the risk for suicidal ideation expressed as adjusted odd ratios (ORs) with 95% confidence intervals (95%CIs)., Results: The risk of suicidal ideation was significantly higher in women who experienced more than three abortions (27.9%). While the incidence of suicidal ideation was not significantly affected by the number of spontaneous abortions (p = 0.718), suicidal ideation was significantly more frequent in women who had undergone ≥ three abortions (p = 0.003). After adjusting for demographic confounding factors, women who underwent ≥ three induced abortions had higher risk for suicidal ideation (OR: 1.510; 95% CI: 1.189-1.919; p = 0.031). This risk remained elevated even after controlling for depression (OR: 1.391; 95% CI: 1.1086-1.871, p = 0.002). Moreover, the risk of experiencing a depressive mood in daily life was also increased with increasing number of induced abortions even after controlling for depression (OR: 1.657; 95% CI: 1.274-2.156, p = 0.002)., Conclusion: Undergoing three or more induced abortions during reproductive age was associated with postmenopausal suicidal ideation, stress, and depression. However, such association was not noted in those with spontaneous abortion, even in women with more miscarriages. Thus, clinicians should evaluate depression and suicidal ideation in women with multiple induced abortions., (Copyright © 2018. Published by Elsevier B.V.)

Purpose: To investigate the effect of oncostatin M (OSM) on protein expression levels and enzymatic activities of matrix metalloprotainase (MMP)-2 and MMP-9 in primary trophoblasts and the invasiveness thereof under normoxia and hypoxia conditions., Materials and Methods: Protein expression levels and enzymatic activities of MMP-2 and MMP-9 in primary trophoblasts under normoxia and hypoxia conditions were examined by Western blot and zymography, respectively. Effects of exogenous OSM on the in vitro invasion activity of trophoblasts according to oxygen concentration were also determined. Signal transducer and activator of transcription 3 (STAT3) siRNA was used to determine whether STAT3 activation in primary trophoblasts was involved in the effect of OSM., Results: OSM enhanced protein expression levels and enzymatic activities of MMP-2 and MMP-9 in term trophoblasts under hypoxia condition, compared to normoxia control (p<0.05). OSM-induced MMP-2 and MMP-9 enzymatic activities were significantly suppressed by STAT3 siRNA silencing under normoxia and hypoxia conditions (p<0.05). Hypoxia alone or OSM alone did not significantly increase the invasiveness of term trophoblasts. However, the invasion activity of term trophoblasts was significantly increased by OSM under hypoxia, compared to that without OSM treatment under normoxia., Conclusion: OSM might be involved in the invasiveness of extravillous trophoblasts under hypoxia conditions via increasing MMP-2 and MMP-9 enzymatic activities through STAT3 signaling. Increased MMP-9 activity by OSM seems to be more important in primary trophoblasts., Competing Interests: The authors have no financial conflicts of interest., (© Copyright: Yonsei University College of Medicine 2018.)

Background: The purpose of this study was to compare the fetal/infant mortality risk associated with each additional week of expectant management to that associated with immediate delivery in women with multiple gestations., Methods: This was a retrospective national cohort study of 94,170 multiple deliveries, 92,619 (98.4%) twin and 1,352 (1.44%) triplet pregnancies, between 32 0/7 and 42 6/7 weeks of gestation recorded in the Korean vital statistics database. We investigated the risks of stillbirth and infant death after birth in Korea according to the week of gestation in twin and triplet pregnancies., Results: The risk of stillbirth significantly increased between 34 and 35 weeks of gestation and between 37 and 38 weeks of gestation in twin pregnancies and between 34 and 37 weeks of gestation in triplet pregnancies. The risk of infant death following delivery gradually decreased as pregnancies approached full term. Week-by-week differences were statistically significant between 33 and 34 weeks, with decreasing risks of infant death at advancing gestational ages in twin pregnancies. At 37 weeks of gestation, the relative risk of mortality was significantly higher with expectant management compared with immediate delivery (relative risk, 3.00; 95% confidence interval, 1.41-6.38)., Conclusion: In twin pregnancies, delivery at 37 weeks of gestation can minimize the risks of stillbirth and infant death in uncomplicated cases, although individual maternal and fetal characteristics must be considered when determining the optimal timing of delivery. In multiple pregnancies, close fetal surveillance is needed after 34 weeks of gestation., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2018 The Korean Academy of Medical Sciences.)

Objective: To evaluate the significance of fetal Doppler parameters in predicting adverse neonatal outcomes and the risk of cesarean delivery due to non-reassuring fetal status, in severe small for gestational age (SGA) fetuses of late preterm and term gestation., Methods: Fetal brain and umbilical artery (UmA) Doppler parameters of cerebroplacental ratio (CPR) and UmA pulsatility index (PI) were evaluated in a cohort of 184 SGA fetuses between 34 and 41 weeks gestational age, who were less than the 5th percentile. The risks of neonatal morbidities and cesarean delivery due to non-reassuring fetal status were analyzed., Results: Univariate analysis revealed that abnormal CPR was significantly associated with cesarean delivery due to non-reassuring fetal status ( P =0.018), but not with neonatal morbidities. However, abnormal CPR did not increase the risk of cesarean delivery due to non-reassuring fetal status in multivariate logistic regression analysis. Abnormal CPR with abnormal PI of UmA was associated with low Apgar score at 1 minute ( P =0.048), mechanical ventilation ( P =0.013) and cesarean delivery due to non-reassuring fetal status ( P <0.001), in univariate analysis. It increased risk of cesarean delivery for non-reassuring fetal status (adjusted odds ratio, 7.0; 95% confidence interval, 1.2-41.3; P =0.033), but did not increase risk of low Apgar score or mechanical ventilation in multivariate logistic regression analysis., Conclusion: Abnormal CPR with abnormal PI of UmA increases the risk of cesarean delivery for non-reassuring fetal status, in severe SGA fetuses of late preterm and term. Monitoring of CPR and PI of UmA can help guide management including maternal hospitalization and fetal monitoring., Competing Interests: Conflict of interest: No potential conflict of interest relevant to this article was reported.

Objective: This study investigated the effect of an antenatal corticosteroid (ACS) in preterm small-for-gestational-age (SGA) neonate., Methods: This study was a retrospective cohort study. We compared women who received ACS with unexposed controls and evaluated neonatal complications among those having a singleton SGA neonate born between 29 and 34 complete gestational weeks. The neonates born after 32 weeks of gestation were divided into subgroups. Multivariable logistic regression analysis was performed., Results: A total 82 of the preterm infants met inclusion criteria; 57 (69.5%) were born after 32 weeks of gestation. There were no significant differences in terms of mechanical ventilation, seizure, intracranial hemorrhage, retinopathy of prematurity, necrotizing enterocolitis, feeding difficulty, and neonatal mortality between infants whose mothers received ACS ant those whose mothers did not (all P >0.05). However, newborns whose mothers received ACS exhibited a significantly increased risk of developing respiratory distress syndrome (RDS) (adjusted odds ratio [aOR], 3.271; 95% confidence interval [CI], 1.038-10.305; P =0.043). In case of neonates born beyond 32 weeks of gestation, the risk of neonatal hypoglycemia was significantly higher in women receiving ACS after controlling for confounding factors (aOR, 5.832; 95% CI, 1.096-31.031; P =0.039)., Conclusion: ACS did not improve neonatal morbidities, in SGA neonates delivered between 29 and 34 gestational weeks. Rather, ACS could increase the risk of RDS. In cases of SGA neonate delivered between 32 and 34 complete gestational weeks, the risk of hypoglycemia was significantly increased. The use of ACS in women with preterm SGA infants needs to be evaluated further, especially after 32 weeks' gestation., Competing Interests: Conflict of interest: No potential conflict of interest relevant to this article was reported.

Objective: To analyse the prevalence of fetal and infant deaths due to birth defects in Korea and those trends according to maternal age., Design: Retrospective national cohort study SETTING: Korean Vital Statistics database of the Korean Statistical Information Service, between 2009 and 2015., Participants: 2176 infant deaths and 4343 fetal deaths caused by birth defects, among 3 181 145 total live births and 43 385 fetal deaths during the study periods., Methods: Infant and fetal mortality rates (IMRs and FMRs) by birth defects, from deaths caused by birth defects, were analysed. They were compared, according to maternal age groups: (I) '10-19 years'; (II) '20-29 years'; (III) '30-34 years'; (IV) '35-39 years'; and (V) '40-55 years'., Main Outcome Measures: IMRs and FMRs by birth defects and comparison according to maternal age group., Results: IMRs and FMRs by birth defects were 6.84 per 10 000 live births and 13.47 per 10 000 total births. The most common causes of infant deaths and fetal deaths by birth defect were anomaly of the circulatory system (51.1%, IMR 3.5) and chromosomal abnormality (33.1%, FMR 4.46), respectively. Among groups by maternal age, FMRs by birth defects were significantly higher in groups I and V compared with group III (OR 6.59, 95% CI 3.49 to 12.43; and OR 3.46, 95% CI 1.77 to 6.78, respectively). IMR and FMR by nervous system anomaly were significantly higher in group I at 3.63 (OR 2.0, 95% CI 1.97 to 2.03) and 29.84 (OR 15.04, 95% CI 3.59 to 62.96) compared with 0.32 and 1.97 in group III., Conclusion: FMRs by birth defects were the highest in the extreme maternal age groups. Severe anomalies, except for chromosomal abnormality, were most prevalent in teenage pregnancies., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Objectives: To evaluate the value of volume measurement using 3-dimensional sonography for prediction of miscarriage., Methods: We prospectively enrolled 188 singleton pregnant women at 5 to 9 weeks' gestation. The 3-dimensional sonographic gestational sac volume and yolk sac volume were measured together with the fetal heart rate, gestational sac diameter, and yolk sac diameter. For each sonographic parameter, nomograms were created; z scores were calculated for each measurement, and the values were compared between miscarriage and ongoing pregnancy groups. Sonographic parameters for prediction of miscarriage were evaluated by multivariate analysis, and the screening performance was assessed by a receiver operating characteristic curve., Results: Among the 188 pregnancies, 30 (16.0%) had miscarriage. Multivariate analysis showed that fetal heart rate below the 5th percentile (odds ratio, 6.43), gestational sac diameter below the 5th percentile (odds ratio, 4.87), gestational sac volume below the 5th percentile (odds ratio, 5.25), and yolk sac diameter below the 2.5th or above the 97.5th percentile (odds ratio, 15.86) were significant predictors of miscarriage (P = .018; P = .018; P = .033; and P < .001, respectively). At a false-positive rate of 30%, the detection rate for miscarriage in screening by a combination of fetal heart rate, gestational sac diameter, gestational sac volume, and yolk sac diameter was 77.8%., Conclusions: A small-for-gestational-age gestational sac volume is a significant sonographic predictor of miscarriage, as are fetal bradycardia, a small gestational sac diameter, and a small or large yolk sac diameter., (© 2015 by the American Institute of Ultrasound in Medicine.)

Purpose: The adult tetanus, reduced diphtheria, and acellular pertussis (Tdap) vaccine has been introduced in order to provide individual protection and reduce the risk of transmitting pertussis to infants. We assessed the knowledge and acceptability of the Tdap vaccine around pregnancy., Materials and Methods: This study was a cross-sectional survey of women of childbearing age (20-45 years) who visited obstetrics and gynecologic units of primary, secondary, or tertiary hospitals. They were asked to fill in a questionnaire assessing their knowledge, attitudes, and acceptability of Tdap., Results: The questionnaire was completed by 308 women; 293 (95.1%) had not received information from doctors about Tdap, and 250 (81.2%) did not know about the need for vaccination. A significantly important factor related to subjects' intention to be vaccinated, identified by stepwise multiple logistic regression, was the knowledge (OR 13.5, CI 3.92-46.33) that adult Tdap is effective in preventing pertussis for infants aged 0-6 months. Additionally, 276 (89.6%) considered the recommendation of obstetric doctors as the most influencing factor about Tdap vaccination., Conclusion: In Korea, most women of childbearing age seem to be neither recommended nor adequately informed about the vaccination, although our population was not a nationwide representative sample. Information given by healthcare workers may be critical for improving awareness and preventing pertussis.