Seroprevalence and placental transfer of SARS-CoV-2 antibodies in unvaccinated pregnant women.

PURPOSE: Pregnant women are at risk of severe SARS-CoV-2 infection, potentially leading to obstetric and neonatal complications. Placental transfer of antibodies directed to SARS-CoV-2 may be protective against neonatal COVID-19, but this remains to be studied. We aimed to determine the seroprevalence of SARS-CoV-2 antibodies in a population of unvaccinated pregnant women and to determine the placental transfer of these antibodies. METHODOLOGY: A total of 1197 unvaccinated women with mostly unknown pre-study SARS-CoV-2 infection status, were tested at delivery for SARS-CoV-2 spike protein IgG antibodies during the first year of the pandemic. Umbilical cord samples were collected and assessed for seropositivity if the mother was seropositive. Maternal characteristics, pregnancy and neonatal outcomes and data on SARS-CoV-2 infection were extracted from medical records. RESULTS: Specific IgG were detected in 258 women (21.6%). A significant placental transfer to the newborn was observed in 81.3% of cases. The earlier in the 2nd and 3rd trimesters that the mother had contracted the disease and the more symptomatic she was, the greater the likelihood of transplacental transfer of IgG to her newborn. CONCLUSION: Approximately one in five women had detectable anti-SARS-CoV-2 spike protein IgG antibodies at delivery during the first year of the pandemic, and these antibodies were significantly transferred to their fetuses. This research provides further evidence to better understand the dynamics of the placental transfer of SARS-CoV-2 IgG antibodies from mothers to their newborns, which is necessary to improve vaccination strategies.

Late miscarriage and stillbirth in asymptomatic and symptomatic hospitalised pregnant women in Belgium during the first and second waves of COVID-19: a prospective nationwide population-based study.

BACKGROUND: Stillbirth has been recognized as a possible complication of a SARS-CoV-2 infection during pregnancy, probably due to destructive placental lesions (SARS-CoV-2 placentitis). The aim of this work is to analyse stillbirth and late miscarriage cases in unvaccinated pregnant women infected with SARS-CoV-2 during the first two waves (wild-type period) in Belgium. METHODS: Stillbirths and late miscarriages in our prospective observational nationwide registry of SARS-CoV-2 infected pregnant women (n = 982) were classified by three authors using a modified WHO-UMC classification system for standardized case causality assessment. RESULTS: Our cohort included 982 hospitalised pregnant women infected with SARS-CoV-2, with 23 fetal demises (10 late miscarriages from 12 to 22 weeks of gestational age and 13 stillbirths). The stillbirth rate was 9.5‰ for singleton pregnancies and 83.3‰ for multiple pregnancies, which seems higher than for the background population (respectively 5.6‰ and 13.8‰). The agreement between assessors about the causal relationship with SARS-Cov-2 infection was fair (global weighted kappa value of 0.66). Among these demises, 17.4% (4/23) were "certainly" attributable to SARS-CoV-2 infection, 13.0% (3/23) "probably" and 30.4% (7/23) "possibly". Better agreement in the rating was noticed when pathological examination of the placenta and identification of the virus were available, underlining the importance of a thorough investigation in case of intra-uterine fetal demise. CONCLUSIONS: SARS-CoV-2 causality assessment of late miscarriage and stillbirth cases in our Belgian nationwide case series has shown that half of the fetal losses could be attributable to SARS-CoV-2. We must consider in future epidemic emergencies to rigorously investigate cases of intra-uterine fetal demise and to store placental tissue and other material for future analyses.

Implementation of fetal clinical exome sequencing: Comparing prospective and retrospective cohorts.

PURPOSE: We compared the diagnostic yield of fetal clinical exome sequencing (fCES) in prospective and retrospective cohorts of pregnancies presenting with anomalies detected using ultrasound. We evaluated factors that led to a higher diagnostic efficiency, such as phenotypic category, clinical characterization, and variant analysis strategy. METHODS: fCES was performed for 303 fetuses (183 ongoing and 120 ended pregnancies, in which chromosomal abnormalities had been excluded) using a trio/duo-based approach and a multistep variant analysis strategy. RESULTS: fCES identified the underlying genetic cause in 13% (24/183) of prospective and 29% (35/120) of retrospective cases. In both cohorts, recessive heterozygous compound genotypes were not rare, and trio and simplex variant analysis strategies were complementary to achieve the highest possible diagnostic rate. Limited prenatal phenotypic information led to interpretation challenges. In 2 prospective cases, in-depth analysis allowed expansion of the spectrum of prenatal presentations for genetic syndromes associated with the SLC17A5 and CHAMP1 genes. CONCLUSION: fCES is diagnostically efficient in fetuses presenting with cerebral, skeletal, urinary, or multiple anomalies. The comparison between the 2 cohorts highlights the importance of providing detailed phenotypic information for better interpretation and prenatal reporting of genetic variants.

The "Cocoon," first alongside midwifery-led unit within a Belgian hospital: Comparison of the maternal and neonatal outcomes with the standard obstetric unit over 2 years.

OBJECTIVES: Our aim was to compare maternal and neonatal outcomes of women with a low-risk pregnancy attending the "Cocoon," an alongside midwifery-led birth center and care pathway, with women with a low-risk pregnancy attending the traditional care pathway in a tertiary care hospital in Belgium. METHODS: We performed a retrospective cohort study of maternal and neonatal outcomes of women with a low-risk pregnancy who chose to adhere to the Cocoon pathway of care (n = 590) and women with a low-risk pregnancy who chose the traditional pathway of care (n = 394) from March 1, 2014, to February 29, 2016. We performed all analyses using an intention-to-treat approach. RESULTS: In this setting, the cesarean birth rate was 10.3% compared with 16.0% in the traditional care pathway (adjusted odds ratios [aOR] 0.42 [95% CI 0.25-0.69]), the induction rate was 16.3% compared with 30.5% (0.46 [0.30-0.69]), the epidural analgesia rate was 24.9% compared with 59.1% (0.15 [0.09-0.22]), and the episiotomy rate was 6.8% compared with 14.5% (0.31 [0.17-0.56]). There was no increase in adverse neonatal outcomes. Intrapartum and postpartum transfer rates to the traditional pathway of care were 21.1% and 7.1%, respectively. CONCLUSIONS: Women planning their births in the midwifery-led unit, the Cocoon, experienced fewer interventions with no increase in adverse neonatal outcomes. Our study gives initial support for the introduction of similar midwifery-led care pathways in other hospitals in Belgium.

Change in prevalence of gestational diabetes and obstetric complications when applying IADPSG screening criteria in a Belgian French speaking University Hospital. A retrospective cohort study.

BACKGROUND: In April 2012 our institution chose to switch from a two- step criteria for Gestational Diabetes Mellitus (GDM) screening, to the International Association of Diabetes in Pregnancy Study Group (IADSPG) criteria. This shift led to an increased prevalence of GDM in our pregnant population. We designed a study in order to estimate the magnitude of the increase in GDM prevalence before and after the switch in screening strategy. As a secondary objective we wanted to evaluate if there was a significant difference between the two periods in the percentage of maternal and neonatal complications such as gestational hypertensive disorders (GHD), primary cesarean section (pCS), preterm birth, large for gestational age (LGA) newborns, macrosomia, shoulder dystocia, 5' Apgar score less than to 7 at birth, neonatal intensive care unit (NICU) transfer and neonatal hypoglycemia. METHODS: We selected retrospectively 3496 patients who delivered between January 2009 and December 2011 who were screened with the two-step criteria (group A), and compared them to 2555 patients who delivered between January 2013 and December 2014 and who were screened with IADPSG criteria (Group B). We checked patients' electronic files to establish GDM status, baseline characteristics (age, body mass index, nationality, parity) and the presence of maternal and neonatal complications. RESULTS: GDM prevalence increased significantly from group A (3.4%; 95%CI 2.8-4.06%) to group B (16.28%; 95%CI 14.8 -17.7%). In group B there were significantly more non-Belgian and primiparous patients. There was no statistically significant difference in maternal and neonatal complications between the two groups, even after adjustment for nationality and parity. There was a non-significant reduction of the proportion of macrosomic and of LGA babies. CONCLUSIONS: In our population the introduction of IADPSG screening criteria has increased the prevalence of GDM without having a statistically significant impact on pregnancy outcomes.

Training for breech deliveries with the mother in an upright position: An innovative adaptation of a simulation model.

BACKGROUND: Delivery of a breech baby with the mother in an upright position or on all fours has gained a renewed interest. In these positions, the obstetrician or midwife needs to learn new landmarks and maneuvers. A realistic simulation model would be a valuable adjunct for breech on all fours teaching programs. MATERIAL AND METHODS: This article describes the simulation model and training program we have developed to train an interprofessional team to assist breech births when the mother is on all fours. A questionnaire was used to evaluate the realism of the adapted mannequin and the impact of training on the confidence level of the participants. RESULTS: On a Likert scale of 1 to 5, 92% of participants agreed or strongly agreed that the adapted mannequin used was realistic for training obstetric maneuvers for complicated breech births. After training, their confidence level supporting a breech birth in an upright position rose from an average of 2.5 to 5.7 on a scale of 1 to 10. CONCLUSION: Learning the skills for breech deliveries on all fours is made possible by targeted training with this adapted simulation model.

First trimester ultrasound prediction of velamentous cord insertions: a prospective study.

INTRODUCTION: The marginal and velamentous cord insertions complicate around 8% of pregnancies and are at higher risk of adverse perinatal outcomes. Their visualisation seems to decrease with advancing gestational age. Our aim was to analyse whether an umbilical cord insertion in the lower third of the uterus during the first trimester could predict abnormal cord insertions later in pregnancy. METHODS: This was a prospective multicentre study in two hospitals. During the first trimester, the cord insertions were inspected as well as their location (lower third of the uterus or not). Finally, all cord insertions were described at delivery. RESULTS: During the study period the cord insertion was described in 1620 patients of which 87.7% had a normal cord insertion, 11.9% (n = 192) a low cord insertion, and in 3.8% the insertion could not be situated. We find that 4.7% of those who have a low-lying cord insertion versus 0.7% in the normal cord insertion group during the first trimester will have a velamentous cord insertion subsequently (OR = 6.67; 95% CI = 2.67-16.63). CONCLUSION: The detection of a low lying umbilical cord insertion during the first-trimester ultrasound can help to predict an abnormal cord insertion at delivery particularly a velamentous cord insertion.