Gender specific intrapartum and neonatal outcomes for term babies

Symptoms of maternal psychological distress during pregnancy: sex-specific effects for neonatal morbidity

OBJECTIVES

Maternal psychological distress during pregnancy has been associated with preterm birth. However, little is known about the relationship of a woman's psychological symptoms during pregnancy to the infant's morbidity at birth or any differential effects of these symptoms on female vs. male fetuses. Our research aims addressed these gaps.

METHODS

A total of 186 women were enrolled between 24 and 34 weeks gestation when demographic information was acquired and they completed the Brief Symptom Inventory to measure psychological distress. Data on gestational age at birth, fetal sex, and neonatal morbidity was extracted from the medical record. To control for their effects, obstetric complications were also identified. Multiple linear regressions were computed to examine the aims, including interaction terms to measure moderating effects of fetal sex.

RESULTS

Symptoms of maternal psychological distress were a significant predictor of neonatal morbidity but were not associated with gestational age. The interaction between symptom distress and fetal/infant sex was also significant for neonatal morbidity but not for gestational age. For boys, high levels of maternal symptom distress during pregnancy were associated with neonatal resuscitation, ventilatory assistance, and infection. Maternal distress was not associated with neonatal morbidity for girls.

CONCLUSIONS

The male fetus may be more sensitive to effects of mothers' psychological symptoms than the female fetus. Further research is needed to confirm our findings and identify potential biological mechanisms that may be responsible for these sex differences. Findings suggest the importance of symptom screening and early intervention to reduce maternal distress and risk of neonatal morbidity.

Association between fetal sex and pregnancy outcomes among women with twin pregnancies: a multicenter cross-sectional study

PURPOSE

To examine the frequency and to what extent fetal sex is associated with pregnancy outcomes among twin pregnancies, stratified by chorionicity.

METHODS

This registry-based multicenter cross-sectional study was conducted using the Japan Society of Obstetrics and Gynecology perinatal database between 2007 and 2016. The sample population was restricted to women with twin pregnancies. The main pregnancy-related outcomes included preterm birth, very preterm birth, extremely preterm birth, preeclampsia, twin-to-twin transfusion syndrome (TTTS), and selective intrauterine growth restriction (s-IUGR). Birth weight, small for gestational age (SGA), and fetal death were also investigated.

RESULTS

The primary analysis was performed based on 37,953 women, including 23,804 women with dichorionic diamniotic (DD) twins and 14,149 women with monochorionic diamniotic (MD) twins. Women with male/male DD twins had a significantly higher risk of preterm birth (adjusted risk ratio [aRR]: 1.07, 95% confidence interval [CI]: 1.03-1.10) and a lower risk of preeclampsia (aRR: 0.74, 95% CI: 0.62-0.88) than women with female/female DD twins. Women with male/male MD twins also had a significantly higher risk of preterm birth (aRR: 1.06, 95% CI: 1.04-1.09) than women with female/female MD twins. Risks of preeclampsia, TTTS, and s-IUGR did not differ by sex among MD pregnancies. Male SGA risk was significantly higher among male/male twins than among male/female DD twins. Among MD twins, risks of SGA and fetal death were significantly higher in male/male fetuses.

CONCLUSIONS

This study demonstrated significant associations between fetal sex and several pregnancy outcomes in twin pregnancies, some of which differed by chorionicity.

Prevalence and factors associated with caesarean section in Rwanda: a trend analysis of Rwanda demographic and health survey 2000 to 2019-20

BACKGROUND

Caesarean section (CS) is an important medical intervention for reducing the risk of poor perinatal outcomes. However, CS trends in sub-Saharan Africa (SSA) continue to increase yet maternal and neonatal mortality and morbidity remain high. Rwanda, like many other countries in SSA, has shown an increasing trend in the use of CS. This study assessed the trends and factors associated with CS delivery in Rwanda over the past two decades.

METHODS

We used nationally representative child datasets from the Rwanda Demographic and Health Survey 2000 to 2019-20. All births in the preceding 3 years to the survey were assessed for the mode of delivery. The participants' characteristics, trends and the prevalence of CS were analysed using frequencies and percentages. Unadjusted and adjusted logistic regression analyses were used to assess the factors associated with population and hospital-based CS in Rwanda for each of the surveys.

RESULTS

The population-based rate of CS in Rwanda significantly increased from 2.2% (95% CI 1.8-2.6) in 2000 to 15.6% (95% CI 13.9-16.5) in 2019-20. Despite increasing in all health facilities over time, the rate of CS was about four times higher in private (60.6%) compared to public health facilities (15.4%) in 2019-20. The rates and odds of CS were disproportionately high among women of high socioeconomic groups, those who resided in Kigali city, had multiple pregnancies, and attended at least four antenatal care visits while the odds of CS were significantly lower among multiparous women and those who had female babies.

CONCLUSION

Over the past two decades, the rate of CS use in Rwanda increased significantly at health facility and population level with high regional and socio-economic disparities. There is a need to examine the disparities in CS trends and developing tailored policy guidelines to ensure proper use of CS in Rwanda.

Which is the best ultrasound parameter for the prediction of adverse perinatal outcome within 1 day of delivery?

OBJECTIVE

To compare the accuracies of several sonographic parameters for the prediction of adverse perinatal outcome (APO) prior to delivery.

METHODS

This was a prospective study of fetuses attending the day hospital unit of a tertiary referral hospital that were scanned at 34-41 weeks and gave birth within 24 h of examination. APO was defined as a composite of abnormal intrapartum fetal heart rate or intrapartum fetal scalp pH < 7.20 requiring urgent cesarean section, neonatal umbilical cord pH < 7.10, 5' Apgar score <7 and postpartum admission to neonatal or pediatric intensive care units. The accuracies of the middle cerebral, vertebral and umbilical arteries pulsatility index multiples of the median (MoM), the cerebroplacental and vertebroplacental ratios MoM and the EFW in centiles for the prediction of APO was evaluated by means of ROC curves and logistic regression analysis.

RESULTS

A total of 2140 fetuses were prospectively scanned, however only 182 entered into spontaneous or induced labor and were delivered within 24 h of examination. In this group, MCA PI MoM was the best predictor of APO (AUC = 0.76, 95% CI 0.66-0.85, p < .0001) followed by the CPR MoM (AUC = 0.73, 95% CI 0.63-0.84, p < .0001) and the VPR MoM (AUC = 0.71, 95% CI 0.61-0.81, p < .001). Logistic regression analysis indicated that MCA PI MoM was the only independent determinant for the prediction of APO.

CONCLUSION

In a high-risk population of third-trimester fetuses delivering within 24 h of examination, the outcome may be moderately anticipated just with the information provided by the cerebral flow.

The Diagnostic Ability of the Cerebroplacental Ratio for the Prediction of Adverse Perinatal Outcome and Intrapartum Fetal Compromise within One Day of Delivery

OBJECTIVES

The objectives of this study were to evaluate the diagnostic abilities of the cerebroplacental ratio (CPR) for the prediction of adverse perinatal outcome (APO) and cesarean section for intrapartum fetal compromise (CS-IFC) within 1 day of delivery.

DESIGN

Retrospective observational case-control study.

METHODS

This was a study of 254 high-risk fetuses attending the day hospital unit of a tertiary referral hospital that underwent an ultrasound examination at 32-41 weeks and gave birth within 1 day of examination. APO was defined as a composite of abnormal intrapartum fetal heart rate or intrapartum fetal scalp pH <7.20 requiring urgent cesarean section, neonatal umbilical cord pH <7.10, 5-min Apgar score <7, and postpartum admission to neonatal or pediatric intensive care units. CS-IFC was defined in case of abnormal intrapartum fetal heart rate or intrapartum fetal scalp pH <7.20 requiring urgent cesarean section. The diagnostic ability of CPR for the prediction of APO and CS-IFC was calculated alone and in combination with estimated fetal weight and gestational clinical parameters, including the type of labor onset, using ROC curves and logistic regression analysis.

RESULTS

CPR in multiples of the median (MoM) was a moderate predictor of APO (area under the curve [AUC] = 0.77, p < 0.0001) and CS-IFC (AUC = 0.82, p < 0.0001). The predictive abilities of the multivariable model for APO (AUC = 0.81, p < 0.0001) and CS-IFC (AUC = 0.82, p < 0.0001) did not differ from those of CPR alone .

LIMITATIONS

The small number of cases and the scarcity of information concerning labor induction.

CONCLUSION

In high-risk pregnancies, CPR MoM is a moderate predictor of APO and CS-IFC when performed within 24 h of delivery.

Sex Differences Are Here to Stay: Relevance to Prenatal Care

Sex differences exist in the incidence and presentation of many pregnancy complications, including but not limited to pregnancy loss, spontaneous preterm birth, and fetal growth restriction. Sex differences arise very early in development due to differential gene expression from the X and Y chromosomes, and later may also be influenced by the action of gonadal steroid hormones. Though offspring sex is not considered in most prenatal diagnostic or therapeutic strategies currently in use, it may be beneficial to consider sex differences and the associated mechanisms underlying pregnancy complications. This review will cover (i) the prevalence and presentation of sex differences that occur in perinatal complications, particularly with a focus on the placenta; (ii) possible mechanisms underlying the development of sex differences in placental function and pregnancy phenotypes; and (iii) knowledge gaps that should be addressed in the development of diagnostic or risk prediction tools for such complications, with an emphasis on those for which it would be important to consider sex.

Neonatal admission and mortality in babies born in UK alongside midwifery units: a national population-based case-control study using the UK Midwifery Study System (UKMidSS)

OBJECTIVES

To determine the incidence of and risk factors for neonatal unit admission, intrapartum stillbirth or neonatal death without admission, and describe outcomes, in babies born in an alongside midwifery unit (AMU).

DESIGN

National population-based case-control study.

METHOD

We used the UK Midwifery Study System to identify and collect data about 1041 women who gave birth in AMUs, March 2017 to February 2018, whose babies were admitted to a neonatal unit or died (cases) and 1984 controls from the same AMUs. We used multivariable logistic regression, generating adjusted OR (aOR) with 95% CIs, to investigate maternal and intrapartum factors associated with neonatal admission or mortality.

RESULTS

The incidence of neonatal admission or mortality following birth in an AMU was 1.2%, comprising neonatal admission (1.2%) and mortality (0.01%). White 'other' ethnicity (aOR=1.28; 95% CI=1.01 to 1.63); nulliparity (aOR=2.09; 95% CI=1.78 to 2.45); ≥2 previous pregnancies ≥24 weeks' gestation (aOR=1.38; 95% CI=1.10 to 1.74); male sex (aOR=1.46; 95% CI=1.23 to 1.75); maternal pregnancy problem (aOR=1.40; 95% CI=1.03 to 1.90); prolonged (aOR=1.42; 95% CI=1.01 to 2.01) or unrecorded (aOR=1.38; 95% CI=1.05 to 1.81) second stage duration; opiate use (aOR=1.31; 95% CI=1.02 to 1.68); shoulder dystocia (aOR=5.06; 95% CI=3.00 to 8.52); birth weight <2500 g (aOR=4.12; 95% CI=1.97 to 8.60), 4000-4999 g (aOR=1.64; 95% CI=1.25 to 2.14) and ≥4500 g (aOR=2.10; 95% CI=1.17 to 3.76), were independently associated with neonatal admission or mortality. Among babies admitted (n=1038), 18% received intensive care. Nine babies died, six following neonatal admission. Sepsis (52%) and respiratory distress (42%) were the most common discharge diagnoses.

CONCLUSIONS

The results of this study are in line with other evidence on risk factors for neonatal admission, and reassuring in terms of the quality and safety of care in AMUs.

Sex differences in uterine artery Doppler during gestation in pregnancies complicated by placental dysfunction

BACKGROUND

There is growing evidence of sex differences in placental vascular development. The objective of this study was to investigate the effect of fetal sex on uterine artery pulsatility index (PI) throughout gestation in a cohort of normal and complicated pregnancies.

METHODS

A prospective longitudinal study was conducted in 240 pregnant women. Pulsed wave Doppler ultrasound of the proximal uterine arteries was performed at a 4-weekly interval between 14 and 40 weeks of gestation. The patients were classified retrospectively as normal or complicated (one or more of maternal preeclampsia, preterm birth, or small for gestational age). To assess if the change in uterine artery PI during gestation differed between normal and complicated pregnancies and between fetal sexes, the uterine artery PI was modeled using a linear function of gestational age and the rate of change was estimated from the slope.

RESULTS

While the uterine artery PI did not differ over gestation between females and males for normal pregnancies, the trajectory of this index differed by fetal sex for pregnancies complicated by either preeclampsia, preterm birth, or fetal growth restriction (p < 0.0001). The male fetuses in the complicated pregnancy group had an elevated slope compared to the other groups (p < 0.0001), suggesting a more progressive deterioration in uteroplacental perfusion over gestation.

CONCLUSIONS

The uterine artery PI is widely used to assess uteroplacental function in clinical settings. The observation that this metric changes more rapidly in complicated pregnancies where the fetus was male highlights the importance of sex when interpreting hemodynamic markers of placental maturation.

Differences in pregnancy complications and outcomes by fetal gender among Japanese women: a multicenter cross-sectional study

The association between fetal gender and rare pregnancy complications has not been extensively investigated, and no studies have examined this association in Japanese women. Thus, we used a large Japanese birth registry database to investigate the extent to which fetal gender affects various pregnancy outcomes. We analyzed 1,098,268 women with a singleton delivery with no congenital anomaly at 22 weeks or later between 2007 and 2015. Women carrying a male fetus had a significantly higher risk of placental abruption (adjusted risk ratio [aRR] 1.15, 95% confidence interval (CI) 1.10–1.20)], preterm delivery (aRR 1.20, 95% CI 1.19–1.22), instrumental delivery (aRR 1.27, 95% CI 1.26–1.29), and cesarean delivery (aRR 1.01, 95% CI 1.00–1.02). In contrast, they had a significantly lower risk of preeclampsia (aRR 0.92, 95% CI 0.89–0.94), placenta accreta (aRR 0.90, 95% CI 0.85–0.96), atonic hemorrhage (aRR 0.95, 95% CI 0.93–0.96), and maternal blood transfusion (aRR 0.95, 95% CI 0.92–0.99). Our findings demonstrate a significant association between fetal gender and various pregnancy complications and delivery outcomes among Japanese women.

Risk factors for perinatal arterial ischaemic stroke: a large case-control study

AIM

To identify maternal, obstetric, and neonatal risk factors related to perinatal arterial ischaemic stroke (PAIS) diagnosed within 28 days after birth and to understand the underlying pathophysiology.

METHOD

For case and control ascertainment, we used active surveillance in 345 paediatric hospitals and a population-based perinatal database for quality assurance of hospital care. We analysed complete cases of PAIS using logistic regression. Multivariate analysis was guided by a directed acyclic graph.

RESULTS

After exclusion of records with missing data, we analysed 134 individuals with PAIS and 576 comparison individuals. In univariate analysis, male sex, preterm birth (<37wks gestational age), small for gestational age (SGA), low umbilical artery pH (<7.1), low 5-minute-Apgar score (<7), multiple pregnancies, hypoxia, intubation/mask ventilation, nulliparity, Caesarean section, vaginal-operative delivery, chorioamnionitis, and oligohydramnios were associated with an increased risk. Mutual adjustment yielded male sex (odds ratio [OR] 1.81; 95% confidence interval [CI] 1.20-2.73), multiple birth (OR 3.22; 95% CI 1.21-8.58), chorioamnionitis (OR 9.89; 95% CI 2.88-33.94), preterm birth (OR 1.86; 95% CI 1.01-3.43), and SGA (OR 3.05; 95% CI 1.76-5.28) as independent risk factors.

INTERPRETATION

We confirmed the increased risk in males and the role of chorioamnionitis and SGA for PAIS, pointing to the importance of inflammatory processes and fetal-placental insufficiency. Multiple birth and preterm birth were additional risk factors.

WHAT THIS PAPER ADDS

Chorioamnionitis and small for gestational age (SGA) precede perinatal arterial ischaemic stroke (PAIS). Chorioamnionitis and SGA are independent risk factors for PAIS. Inflammatory processes and fetal-placental insufficiency are the likely underlying mechanisms. Multiple birth and preterm birth are additional risk factors.

Does Fetal Gender Really Affects Neonatal Birth Weight and Gestational Age at Birth? A Prospective Cohort Study

OBJECTIVE

The objective of this study was to understand the impact of fetal gender on neonatal birth weight for the gestational age at the time of birth. Only neonates with a gestational age of 28 weeks or more than 28 weeks were included in the study.

METHODS

This prospective study was conducted within the Obstetrics and Gynecology Department of a rural tertiary center in Northern India. The study was conducted after ethical clearance and informed consent from participants who fulfilled the inclusion criteria. Data collection included neonatal gender, birth weight, Apgar scores, and gestational age. Neonates were delivered vaginally or by cesarean section at 28 or more weeks of gestation. Statistical analysis was done using version SPSS-22 software.

RESULTS

Of 2,997 live fetuses, 1,574 (52.5%) were male, 1,421 (47.4%) were female, and 2 (0.07%) had ambiguous genitalia. Mean ± standard deviation (SD) for male neonate's birth weight was 2.79 ± 0.503 kg (95% confidence interval [CI]: 2.76–2.81), for females 2.67 ± 0.485 kg (95% CI: 2.64–2.69) respectively (p = .000). Males had lower Apgar scores at 1 and 5 minutes of age compared to females (7.06 ± 0.859, 8.83 ± 0.838 vs. 7.12 ± 0.645, 8.88 ± 0.612). There were no significant difference between fetal gender and gestational age at birth (18% females were preterm vs. 15.4% males, 81.8% females were term vs. 84.2% males, 0.1% females post-term vs. 0.4% males; p = .079).

CONCLUSION

Fetal gender was related to birth weight. Male neonates had a higher birth weight, but lower Apgar scores than female neonates. Fetal gender was not correlated with gestational age at the time of birth.

Maternal Distress During Pregnancy and Recurrence in Early Childhood Predicts Atopic Dermatitis and Asthma in Childhood

BACKGROUND

Early-life stress is becoming an important determinant of immune system programming. Maternal prenatal distress is found to be associated with atopic disease in offspring but the separate effects of postnatal distress are not well-studied.

RESEARCH QUESTION

Does the likelihood of asthma and atopic dermatitis in children increase when they are exposed to maternal distress pre- and postnatally in a sex-specific manner?

STUDY DESIGN AND METHODS

Using data from a provincial newborn screen and health-care database for 12,587 children born in 2004, maternal distress (depression or anxiety) was defined as prenatal, self-limiting, recurrent, or late-onset postpartum. Atopic dermatitis (AD) and asthma at ages 5 years and 7 years of age were diagnosed by using hospitalization, physician visit, or prescription records. Associations between maternal distress and childhood asthma and AD were determined by using multiple logistic regression.

RESULTS

After adjusting for risk factors, a significant association between maternal prenatal (OR, 1.27; 95% CI, 1.11-1.46), recurrent postpartum (OR, 1.28; 95% CI, 1.11-1.48), and late-onset postpartum (OR, 1.19, 95% CI, 1.06-1.34) distress was found with AD at age 5 years. Asthma at age 7 years was also associated with maternal prenatal distress (OR, 1.57; 95% CI, 1.29-1.91) and late-onset postnatal distress (OR, 1.22; 95% CI, 1.01-1.46). Self-limiting postnatal distress was not found to be a risk factor for either atopic condition. Associations with AD or asthma were of a similar magnitude in boys and girls; the exception was recurrent postnatal distress, which increased risk for asthma in boys only.

INTERPRETATION

This population-based study provides evidence for sex-specific associations between maternal prenatal and postnatal distress, as well as the development of AD and asthma. The findings support recommendations for greater psychosocial support of mothers during pregnancy and early childhood to prevent childhood atopic disease.

Intrapartum hypoxia and sexual dimorphism in adverse perinatal outcomes

OBJECTIVES

The aim of this study is to evaluate whether markers of intrapartum hypoxia differ according to sex, and if this could explain the increased risk of adverse perinatal outcomes in males.

STUDY DESIGN

This is a retrospective observational cohort study of non-anomalous, singleton deliveries >36 completed weeks' gestation at a UK teaching hospital over a 4.5 year period. Absent or incomplete cord gas results were excluded and the remaining data were validated according to an established method. The relations between sex and both arterial pH and a composite variable, 'fetal distress' (cases in which operative delivery or caesarean section were undertaken for presumed fetal compromise), were examined using independent samples t-test and Chi-square test. Odds ratios with 95 % confidence intervals were calculated to describe the relation between fetal sex and intermediate-term adverse outcomes. Binary logistic regression was performed to generate odds ratios (with 95 % confidence intervals) adjusted for arterial pH and fetal distress. This was repeated to adjust for labor and induction of labor.

RESULTS

There were eligible 8758 cases, of which 4655 were male and 4103 female, from a total of 39,148 deliveries during the study period. Neonatal unit admission (OR 1.54, 95 % CI; 1.31-1.80), renal impairment (OR 1.63, 95 % CI; 1.15-2.32), neurological impairment (OR 1.73, 95 % CI; 1.06-2.84) and a composite adverse outcome (OR 1.73, 95 % CI; 1.29-2.33) were all more likely in males, even after adjusting for labor and induction of labor, both of which were more likely males. The mean cord arterial pH of males was lower (7.23 vs 7.24, P = 0.019) although they were not more likely to be acidemic with a pH <7.0 (males 43 (0.92 %) vs females 41 (1.00 %), P = 0.717), and males were also more likely to have fetal distress (834 (17.9 %) vs 588 (14.3 %), P = <0.001). Being male remained associated with adverse outcomes despite adjustment for arterial pH and fetal distress.

CONCLUSION

Despite a lower mean cord arterial pH and greater incidence of fetal distress in males, intrapartum hypoxia does not account for their worse neonatal outcomes.

Ovine prenatal growth-restriction and sex influence fetal adipose tissue phenotype and impact postnatal lipid metabolism and adiposity in vivo from birth until adulthood

Adipose tissue development begins in utero and is a key target of developmental programming. Here the influence of nutritionally-mediated prenatal growth-restriction on perirenal adipose tissue (PAT) gene expression and adipocyte phenotype in late fetal life was investigated in both sexes in an ovine model. Likewise circulating leptin concentrations and non-esterified fatty acid (NEFA) and glycerol responses to glucose challenge were determined in relation to offspring adiposity at key stages from birth to mid-adult life. In both studies' singleton-bearing adolescent sheep were fed control or high nutrient intakes to induce normal or growth-restricted pregnancies, respectively. Fetal growth-restriction at day 130 of gestation (32% lighter) was characterised by greater body-weight-specific PAT mass and higher PAT expression of peroxisome proliferator-activated receptor gamma (PPARɤ), glycerol-3-phosphate dehydrogenase, hormone sensitive lipase (HSL), insulin-like growth factor 1 receptor, and uncoupling protein 1. Independent of prenatal growth, females had a greater body-weight-specific PAT mass, more multilocular adipocytes, higher leptin and lower insulin-like growth factor 1 mRNA than males. Growth-restricted offspring of both sexes (42% lighter at birth) were characterised by higher plasma NEFA concentrations across the life-course (post-fasting and after glucose challenge at 7, 32, 60, 85 and 106 weeks of age) consistent with reduced adipose tissue insulin sensitivity. Circulating plasma leptin correlated with body fat percentage (females>males) and restricted compared with normal females had more body fat and increased abundance of PPARɤ, HSL, leptin and adiponectin mRNA in PAT at necropsy (109 weeks). Therefore, prenatal nutrient supply and sex both influence adipose tissue development with consequences for lipid metabolism and body composition persisting throughout the life-course.

Prediction of emergency cesarean section by measurable maternal and fetal characteristics

Objective

To analyze the maternal and fetal factors affecting emergency cesarean section (EmCS) and establish a risk scoring system to quantitatively predict the risk of EmCS.

Design

A total of 10,295 pregnant women were enrolled in this study. The influence of maternal and fetal factors on the risk of EmCS was analyzed.

Results

991 (9.63%) cases of failed vaginal delivery received EmCS. The two main causes of EmCS were fetal distress (67.21%) and abnormal fetal position (14.93%). There were significant differences in 17 maternal and fetal factors between the normal vaginal delivery (NVD) and EmCS groups (p<0.05 for all). Univariate and multivariate regression analyses showed that nine maternal and infant factors were independent risk factors (p<0.05 for all). The major factors were abnormal quantity of amniotic fluid (OR 6.867, 95% CI 4.442 to 10.618), nulliparous (OR 4.336, 95% CI 3.074 to 6.115), induction of labor (OR 5.300, 95% CI 4.514 to 6.224) and abnormal characters of amniotic fluid (OR 3.126, 95% CI 2.708 to 3.608). A risk scoring system (six grades) was established based on those factors which showed high discriminative power. The rate of EmCS was 1.30%, 2.57%, 5.83%, 13.94%, 21.75% and 39.71% in grades 1, 2, 3, 4, 5 and 6, respectively. The area under the curve of the risk scoring system was 0.787, indicating that the regression model of the risk factors had a good predictive ability.

Conclusion

An effective risk scoring system has been developed to quantitatively assess the risk of EmCS based on measurable maternal and fetal factors. The system is simple, easy to operate and has good repeatability in clinical practice.

Adherence to guidelines and suboptimal practice in term breech delivery with perinatal death- a population-based case-control study in Norway

BACKGROUND

In a recent population-based study we reported excess risk of neonatal mortality associated with vaginal breech delivery. In this case-control study we examine whether deviations from Norwegian guidelines are more common in breech deliveries resulting in intrapartum or neonatal deaths than in breech deliveries where the offspring survives, and if these deaths are potentially avoidable.

MATERIAL AND METHODS

Case-control study completed as a perinatal audit including term breech deliveries of singleton without congenital anomalies in Norway from 1999 to 2015. Deliveries where the child died intrapartum or in the neonatal period were case deliveries. For each case, two control deliveries who survived were identified. All the included deliveries were reviewed by four obstetricians independently assessing if the deaths in the case group might have been avoided and if the management of the deviations from Norwegian guidelines were more common in case than in control deliveries.

RESULTS

Thirty-one case and 62 control deliveries were identified by the Medical Birth Registry of Norway. After exclusion of non-eligible deliveries, 22 case and 31 control deliveries were studied. Three case and two control deliveries were unplanned home deliveries, while all in-hospital deliveries were in line with national guidelines. Antenatal care and/or management of in-hospital deliveries was assessed as suboptimal in seven (37%) case and two (7%) control deliveries (p = 0.020). Three case deliveries were completed as planned caesarean delivery and 12 (75%) of the remaining 16 deaths were considered potentially avoidable had planned caesarean delivery been done. In seven of these 16 deliveries, death was associated with cord prolapse or difficult delivery of the head.

CONCLUSION

All in-hospital breech deliveries were in line with Norwegian guidelines. Seven of twelve potentially avoidable deaths were associated with birth complications related to breech presentation. However, suboptimal care was more common in case than control deliveries. Further improvement of intrapartum care may be obtained through continuous rigorous training and feedback from repeated perinatal audits.

Sex differences in fetal growth and immediate birth outcomes in a low-risk Caucasian population

Background

According to the WHO Multicentre Growth Reference Study Group recommendations, boys and girls have different growth trajectories after birth. Our aim was to develop gender-specific fetal growth curves in a low-risk population and to compare immediate birth outcomes.

Methods

First, second, and third trimester fetal ultrasound examinations were conducted between 2002 and 2012. The data was selected using the following criteria: routine examinations in uncomplicated singleton pregnancies, Caucasian ethnicity, and confirmation of gestational age by a crown-rump length (CRL) measurement in the first trimester. Generalized Additive Model for Location, Scale and Shape (GAMLSS) was used to align the time frames of the longitudinal fetal measurements, corresponding with the methods of the postnatal growth curves of the WHO MGRS Group.

Results

A total of 27,680 complete scans were selected from the astraia© ultrasound database representing 12,368 pregnancies. Gender-specific fetal growth curves for biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) were derived. The HC and BPD were significantly larger in boys compared to girls from 20 weeks of gestation onwards (p < 0.001) equating to a 3-day difference at 20–24 weeks. Boys were significantly heavier, longer, and had greater head circumference than girls (p < 0.001) at birth. The Apgar score at 1 min (p = 0.01) and arterial cord pH (p < 0.001) were lower in boys.

Conclusions

These longitudinal fetal growth curves for the first time allow integration with neonatal and pediatric WHO gender-specific growth curves. Boys exceed head growth halfway of the pregnancy, and immediate birth outcomes are worse in boys than girls. Gender difference in intrauterine growth is sufficiently distinct to have a clinically important effect on fetal weight estimation but also on the second trimester dating. Therefore, these differences might already play a role in early fetal or immediate neonatal management.

Electronic supplementary material

The online version of this article (10.1186/s13293-019-0261-7) contains supplementary material, which is available to authorized users.

Early Sex Differences in the Immune-Inflammatory Responses to Neonatal Ischemic Stroke

We recently reported that neonatal ischemia induces microglia/macrophage activation three days post-ischemia. We also found that female mice sustained smaller infarcts than males three months post-ischemia. The objective of our current study was to examine whether differential acute neuroinflammatory response and infiltrated immune cells occurs between male and females after three days post-ischemia. Permanent middle cerebral artery occlusion was induced in male and female postnatal 9-day-old (P9) mice, and mice were sacrificed three days after ischemia. Brains were analyzed for mRNA transcription after microglia magnetic cell sorting to evaluate M1 and M2 markers. FACS analysis was performed to assess myeloid infiltration and microglial expression of CX3 chemokine receptor 1 (CX3CR1). Inflammatory cytokine expression and microglia/macrophage activation were analyzed via in situ hybridization combined with immunofluorescence techniques. Lesion volume and cell death were measured. An increase in microglia/macrophages occurred in male versus female mice. The cells exhibited amoeboid morphology, and TNFα and ptgs2 (Cox-2) genes were more expressed in males. More myeloid cell infiltration was found in male versus female brains. However, we did not observe sex-dependent differences in the injured volume or cell death density. Our data show that sex differences in the acute microglial and immune responses to neonatal ischemia are likely both gene- and region-specific.

Boys and girls differ in symptoms and neurodevelopmental outcome after perinatal metabolic acidosis, a population-based study

AIM

To evaluate sex differences in infants born at term with metabolic acidosis with regard to perinatal health and symptomatology, and developmental outcome.

METHODS

From a population-based cohort of infants born at term (n = 14 687), 78 were prospectively identified as having metabolic acidosis at birth. Two matched controls per case were selected. Sex differences in perinatal characteristics and in neurodevelopmental outcome at 6.5 years of age were analysed. Subgroup analysis was made based on need of neonatal care and planned follow-up.

RESULTS

Acidotic boys who appeared healthy, that is with no need of specialised neonatal care respectively only followed at ordinary health care service, have worse perinatal symptoms and less favourable neurodevelopmental outcome compared to girls. The male disadvantage concerning neurodevelopmental outcome was also indicated in children without acidosis. Outcome at 6.5 years was associated with Apgar at 10 minutes (p = 0.03), need of neonatal care (p = 0.04) and sex (p = 0.02) but not acidosis per se (p = 0.54).

CONCLUSION

Sex affected immediate symptomatology in term acidotic infants and neurodevelopmental outcome at the age of 6.5 years. The findings were seen in those who appeared healthy in the neonatal period. The results suggest that sex should be considered in assessment of acidotic children.

Sex differences in umbilical artery Doppler indices: a longitudinal study

Background

Sexual dimorphism in placental size and function has been described. Whether this influences the clinically important umbilical artery (UA) waveform remains controversial, although a few cross-sectional studies have shown sex differences in UA pulsatility index (PI). Therefore, we tested whether fetal sex influences the UA Doppler indices during the entire second half of pregnancy and aimed to establish sex-specific reference ranges for UA Doppler indices if needed.

Methods

Our main objective was to investigate gestational age-associated changes in UA Doppler indices during the second half of pregnancy and compare the values between male and female fetuses. This was a prospective longitudinal study in women with singleton low-risk pregnancies during 19–40 weeks of gestation. UA Doppler indices were serially obtained at a 4-weekly interval from a free loop of the umbilical cord using color-directed pulsed-wave Doppler ultrasonography. Sex-specific reference intervals were calculated for the fetal heart rate (HR), UA PI, resistance index (RI), and systolic/diastolic ratio (S/D) using multilevel modeling.

Results

Complete data from 294 pregnancies (a total of 1261 observations from 152 male and 142 female fetuses) were available for statistical analysis, and sex-specific reference ranges for the UA Doppler indices and fetal HR were established for the last half of pregnancy. UA Doppler indices were significantly associated with gestational age (P < 0.0001) and fetal HR (P < 0.0001). Female fetuses had 2–8% higher values for UA Doppler indices than male fetuses during gestational weeks 20⁺⁰–36⁺⁶ (P < 0.05), but not later. Female fetuses had higher HR from gestational week 26⁺⁰ until term (P < 0.05).

Conclusions

We have determined gestational age-dependent sex differences in UA Doppler indices and fetal HR during the second half of pregnancy, and correspondingly established new sex-specific reference ranges intended for refining diagnostics and monitoring individual pregnancies.

The Effect of Fetal Gender on the Delivery Outcome in Primigravidae Women with Induced Labours for all Indications

INTRODUCTION

There is increasing evidence of a gender-related phenomenon where the presence of a male fetus may have an adverse effect on the outcome of pregnancy.

AIM

The aim of this study was to investigate the effect of fetal gender on the delivery outcome in primigravidae women with induced labours.

MATERIALS AND METHODS

This was an observational cohort study of primigravidae women who had Induction Of Labour (IOL) for all indications during a two-year period. Women with breech vaginal deliveries, stillbirths, multiple pregnancies and elective Caesarean Section (CS) were excluded.

RESULTS

Of the 936 eligible patients identified, 493(52.6%) gave birth to male neonates and 443(47.4%) to female neonates. Age, ethnicity, Body Mass Index (BMI) and smoking were similar between women that delivered male and female neonates. More than half of all women were induced for post-date pregnancies. In women who gave birth to male neonates, the CS delivery rate was higher than in those with female neonates (23.7% vs 17.8%; p=0.029). Though emergency admission rates to the neonatal Intensive Care Unit (ICU) and arterial/venous pH from umbilical cord sampling immediately after birth were similar between male and female neonates, nevertheless male neonates had lower Apgar scores of <7 at 1 minute after birth (p=0.02).

CONCLUSIONS

This study has shown that, male gender fetuses have a higher CS delivery rate in primigravidae women undergoing IOL and may be more vulnerable to fetal compromise when in labour.

Exploring sexual dimorphism in placental circulation at 22-24 weeks of gestation: A cross-sectional observational study

INTRODUCTION

Placental blood flow is closely associated with fetal growth and wellbeing. Recent studies suggest that there are differences in blood flow between male and female fetuses. We hypothesized that sexual dimorphism exists in fetal and placental blood flow at 22-24 weeks of gestation.

METHODS

This was a prospective cross-sectional study of 520 healthy pregnant women. Blood flow velocities of the middle cerebral artery (MCA), umbilical artery (UA), umbilical vein (UV) and the uterine arteries (UtA) were measured using Doppler ultrasonography. UV and UtA diameters were measured using two-dimensional ultrasonography and power Doppler angiography. Volume blood flows (Q) of the UV and UtA were calculated. Maternal haemodynamics was assessed with impedance cardiography. UtA resistance (R_uta) was computed as MAP/Q_uta.

RESULTS

UA PI was significantly (p = 0.008) higher in female fetuses (1.19 ± 0.15) compared with male fetuses (1.15 ± 0.14). MCA PI, cerebro-placental ratio (MCA PI/UA PI), Q_uv, UtA PI, Q_uta and R_uta were not significantly different between groups. At delivery, the mean birth weight and placental weight of female infants (3504 g and 610 g) were significantly (p = 0.0005 and p = 0.039) lower than that of the male infants (3642 g and 634 g).

DISCUSSION

We have demonstrated sexual dimorphism in UA PI, a surrogate for placental vascular resistance, at 22-24 weeks of gestation. Therefore, it would be useful to know when this difference emerges and whether it translates into blood flow differences that may impact upon the fetal growth trajectory.

Birth weight centiles, risk of intrapartum compromise, and adverse perinatal outcomes in term infants

OBJECTIVE

The objective of this study is to evaluate the association between birth weight centiles and the risk of intrapartum compromise and adverse neonatal outcomes in term pregnancies.

METHODS

Retrospective study of 32 468 term singleton births at a major tertiary maternity hospital in Australia. Data comprised gestation, mode, and indication for delivery and adverse perinatal outcomes. Fetal sex and gestational age-specific birth weight centiles were the main exposure variable.

RESULTS

Neonates <21st birth weight centile had an increased risk of intrapartum compromise, the highest risk was in babies <3rd centile (OR 4.04, 95% CI 3.34-4.89). The risk of adverse perinatal outcomes was increased in neonates <21st and >91st birth weight centiles. The highest risk was in those <3rd centile (OR 2.35, 95% CI 2.00-2.75).

CONCLUSIONS

Fetal size measurements near term may be used as part of screening test for identifying fetuses at an increased risk of intrapartum compromise and adverse perinatal outcomes.

Risk Factors for Neonatal Arterial Ischemic Stroke: The Importance of the Intrapartum Period

OBJECTIVE

To investigate risk factors for neonatal arterial ischemic stroke (NAIS), and compare them with those present in term controls and infants with hypoxic-ischemic encephalopathy (HIE).

STUDY DESIGN

Antepartum and intrapartum data were collected at presentation from 79 infants with NAIS and compared with 239 controls and 405 infants with HIE. The relationships between risk factors and NAIS were explored using univariable and multivariable regression.

RESULTS

Compared with controls, infants with NAIS more frequently had a family history of seizures/neurologic diseases, primiparous mothers, and male sex. Mothers of infants with NAIS experienced more intrapartum complications: prolonged rupture of membranes (21% vs 2%), fever (14% vs 3%), thick meconium (25% vs 7%), prolonged second stage (31% vs 13%), tight nuchal cord (15% vs 6%), and abnorm8al cardiotocography (67% vs 21%). Male sex (OR 2.8), family history of seizures (OR 6.5) or neurologic diseases (OR 4.9), and ≥1 (OR 5.8) and ≥2 (OR 21.8) intrapartum complications were independently associated with NAIS. Infants with NAIS and HIE experienced similar rates though different patterns of intrapartum complications. Maternal fever, prolonged rupture of membranes, prolonged second stage, tight nuchal cord, and failed ventouse delivery were more common in NAIS; thick meconium, sentinel events, and shoulder dystocia were more frequent in HIE. Abnormal cardiotocography occurred in 67% of NAIS and 77.5% of infants with HIE. One infant with NAIS and no infant with HIE was delivered by elective cesarean (10% of controls).

CONCLUSIONS

NAIS is multifactorial in origin and shares risk factors in common with HIE. Intrapartum events may play a more significant role in the pathogenesis of NAIS than previously recognized.

Foetal Gender and Obstetric Outcome

Introduction: Data on specific characteristics based on the gender of the unborn baby and their significance for obstetrics are limited. The aim of this study is to analyse selected parameters of obstetric relevance in the phases pregnancy, birth and postpartum period in dependence on the gender of the foetus. Materials and Methods: The selected study method comprised a retrospective data acquisition and evaluation from the Austrian birth register of the Department of Clinical Epidemiology of Tyrolean State Hospitals. For the analysis all inpatient singleton deliveries in Austria during the period from 2008 to 2013 were taken into account (live and stillbirths n = 444 685). The gender of the baby was correlated with previously defined, obstetrically relevant parameters. Results: In proportions, significantly more premature births and sub partu medical interventions (vaginal and abdominal surgical deliveries. episiotomies) were observed for male foetuses (p < 0.001). The neonatal outcome (5-min Apgar score, umbilical pH value less than 7.1, transfer to a neonatal special unit) is significantly poorer for boys (p < 0.001). Discussion: In view of the vulnerability of male foetuses and infants, further research is needed in order to be able to react appropriately to the differing gender-specific requirements in obstetrics.