COVID-19 vaccination during pregnancy: coverage and safety.

BACKGROUND: Concerns have been raised regarding a potential surge of COVID-19 in pregnancy, secondary to the rising numbers of COVID-19 in the community, easing of societal restrictions, and vaccine hesitancy. Although COVID-19 vaccination is now offered to all pregnant women in the United Kingdom; limited data exist on its uptake and safety. OBJECTIVE: This study aimed to investigate the uptake and safety of COVID-19 vaccination among pregnant women. STUDY DESIGN: This was a cohort study of pregnant women who gave birth at St George's University Hospitals National Health Service Foundation Trust, London, United Kingdom, between March 1, 2020, and July 4, 2021. The primary outcome was uptake of COVID-19 vaccination and its determinants. The secondary outcomes were perinatal safety outcomes. Data were collected on COVID-19 vaccination uptake, vaccination type, gestational age at vaccination, and maternal characteristics, including age, parity, ethnicity, index of multiple deprivation score, and comorbidities. Further data were collected on perinatal outcomes, including stillbirth (fetal death at ≥24 weeks' gestation), preterm birth, fetal and congenital abnormalities, and intrapartum complications. Pregnancy and neonatal outcomes of women who received the vaccine were compared with that of a matched cohort of women with balanced propensity scores. Effect magnitudes of vaccination on perinatal outcomes were reported as mean differences or odds ratios with 95% confidence intervals. Factors associated with antenatal vaccination were assessed with logistic regression analysis. RESULTS: Data were available for 1328 pregnant women of whom 140 received at least 1 dose of the COVID-19 vaccine before giving birth and 1188 women who did not; 85.7% of those vaccinated received their vaccine in the third trimester of pregnancy and 14.3% in the second trimester of pregnancy. Of those vaccinated, 127 (90.7%) received a messenger RNA vaccine and 13 (9.3%) a viral vector vaccine. There was evidence of reduced vaccine uptake in younger women (P=.001), women with high levels of deprivation (ie, fifth quintile of the index of multiple deprivation; P=.008), and women of Afro-Caribbean or Asian ethnicity compared with women of White ethnicity (P<.001). Women with prepregnancy diabetes mellitus had increased vaccine uptake (P=.008). In the multivariable model the fifth deprivation quintile (most deprived) (adjusted odds ratio, 0.10; 95% confidence interval, 0.02-0.10; P=.003) and Afro-Caribbean ethnicity (adjusted odds ratio, 0.27; 95% confidence interval, 0.06-0.85; P=.044) were significantly associated with lower antenatal vaccine uptake, whereas prepregnancy diabetes mellitus was significantly associated with higher antenatal vaccine uptake (adjusted odds ratio, 10.5; 95% confidence interval, 1.74-83.2; P=.014). In a propensity score-matched cohort, the rates of adverse pregnancy outcomes of 133 women who received at least 1 dose of the COVID-19 vaccine in pregnancy were similar to that of unvaccinated pregnant women (P>.05 for all): stillbirth (0.0% vs 0.2%), fetal abnormalities (2.2% vs 2.5%), postpartum hemorrhage (9.8% vs 9.0%), cesarean delivery (30.8% vs 34.1%), small for gestational age (12.0% vs 12.8%), maternal high-dependency unit or intensive care admission (6.0% vs 4.0%), or neonatal intensive care unit admission (5.3% vs 5.0%). Intrapartum pyrexia (3.7% vs 1.0%; P=.046) was significantly increased but the borderline statistical significance was lost after excluding women with antenatal COVID-19 infection (P=.079). Mixed-effects Cox regression showed that vaccination was not significantly associated with birth at <40 weeks' gestation (hazard ratio, 0.93; 95% confidence interval, 0.71-1.23; P=.624). CONCLUSION: Of pregnant women eligible for COVID-19 vaccination, less than one-third accepted COVID-19 vaccination during pregnancy, and they experienced similar pregnancy outcomes with unvaccinated pregnant women. There was lower uptake among younger women, non-White ethnicity, and lower socioeconomic background. This study has contributed to the body of evidence that having COVID-19 vaccination in pregnancy does not alter perinatal outcomes. Clear communication to improve awareness among pregnant women and healthcare professionals on vaccine safety is needed, alongside strategies to address vaccine hesitancy. These strategies include postvaccination surveillance to gather further data on pregnancy outcomes, particularly after first-trimester vaccination, and long-term infant follow-up.

COVID-19 vaccination in pregnancy.

Despite a recent endorsement from official and professional bodies unequivocally recommending COVID-19 vaccination, vaccine hesitancy among pregnant people remains high. The accumulated evidence demonstrates that pregnant people are a special risk group for COVID-19, with an increased risk of intensive care unit admission, extracorporeal membranous oxygenation requirement, preterm birth, and perinatal death. These risks are further increased with some variants of concern, and vaccination of pregnant people reduces the COVID-19-related increase in maternal or fetal morbidity. Data from more than 180,000 vaccinated persons show that immunization against COVID-19 with an mRNA vaccine is safe for pregnant people. Many observational studies comparing perinatal outcomes between vaccinated and unvaccinated pregnant people have had reassuring findings and did not demonstrate harmful effects on pregnancy or the newborn. Immunization with mRNA vaccines does not increase the risk of miscarriage, preterm delivery, low birthweight, maternal or neonatal intensive care unit admission, fetal death, fetal abnormality, or pulmonary embolism. Moreover, observational data corroborate the findings of randomized trials that mRNA vaccination is highly effective at preventing severe SARS-CoV-2 infection in pregnant people, emphasizing that the potential maternal and fetal benefits of vaccination greatly outweigh the potential risks of vaccination. Ensuring pregnant people have unrestricted access to COVID-19 vaccination should be a priority in every country worldwide.

An internally validated prediction model for critical COVID-19 infection and intensive care unit admission in symptomatic pregnant women.

BACKGROUND: Pregnant women are at an increased risk of mortality and morbidity owing to COVID-19. Many studies have reported on the association of COVID-19 with pregnancy-specific adverse outcomes, but prediction models utilizing large cohorts of pregnant women are still lacking for estimating the risk of maternal morbidity and other adverse events. OBJECTIVE: The main aim of this study was to develop a prediction model to quantify the risk of progression to critical COVID-19 and intensive care unit admission in pregnant women with symptomatic infection. STUDY DESIGN: This was a multicenter retrospective cohort study including 8 hospitals from 4 countries (the United Kingdom, Austria, Greece, and Turkey). The data extraction was from February 2020 until May 2021. Included were consecutive pregnant and early postpartum women (within 10 days of birth); reverse transcriptase polymerase chain reaction confirmed SARS-CoV-2 infection. The primary outcome was progression to critical illness requiring intensive care. The secondary outcomes included maternal death, preeclampsia, and stillbirth. The association between the primary outcome and 12 candidate predictors having a known association with severe COVID-19 in pregnancy was analyzed with log-binomial mixed-effects regression and reported as adjusted risk ratios. All the potential predictors were evaluated in 1 model and only the baseline factors in another. The predictive accuracy was assessed by the area under the receiver operating characteristic curves. RESULTS: Of the 793 pregnant women who were positive for SARS-CoV-2 and were symptomatic, 44 (5.5%) were admitted to intensive care, of whom 10 died (1.3%). The 'mini-COvid Maternal Intensive Therapy' model included the following demographic and clinical variables available at disease onset: maternal age (adjusted risk ratio, 1.45; 95% confidence interval, 1.07-1.95; P=.015); body mass index (adjusted risk ratio, 1.34; 95% confidence interval, 1.06-1.66; P=.010); and diagnosis in the third trimester of pregnancy (adjusted risk ratio, 3.64; 95% confidence interval, 1.78-8.46; P=.001). The optimism-adjusted area under the receiver operating characteristic curve was 0.73. The 'full-COvid Maternal Intensive Therapy' model included body mass index (adjusted risk ratio, 1.39; 95% confidence interval, 1.07-1.95; P=.015), lower respiratory symptoms (adjusted risk ratio, 5.11; 95% confidence interval, 1.81-21.4; P=.007), neutrophil to lymphocyte ratio (adjusted risk ratio, 1.62; 95% confidence interval, 1.36-1.89; P<.001); and serum C-reactive protein (adjusted risk ratio, 1.30; 95% confidence interval, 1.15-1.44; P<.001), with an optimism-adjusted area under the receiver operating characteristic curve of 0.85. Neither model showed signs of a poor fit. Categorization as high-risk by either model was associated with a shorter diagnosis to intensive care unit admission interval (log-rank test P<.001, both), higher maternal death (5.2% vs 0.2%; P<.001), and preeclampsia (5.7% vs 1.0%; P<.001). A spreadsheet calculator is available for risk estimation. CONCLUSION: At presentation with symptomatic COVID-19, pregnant and recently postpartum women can be stratified into high- and low-risk for progression to critical disease, even where resources are limited. This can support the nature and place of care. These models also highlight the independent risk for severe disease associated with obesity and should further emphasize that even in the absence of other comorbidities, vaccination is particularly important for these women. Finally, the model also provides useful information for policy makers when prioritizing national vaccination programs to quickly protect those at the highest risk of critical and fatal COVID-19.

Management and implications of severe COVID-19 in pregnancy in the UK: data from the UK Obstetric Surveillance System national cohort.

INTRODUCTION: There is a lack of population level data on risk factors and impact of severe COVID-19 in pregnancy. The aims of this study were to determine the characteristics, and maternal and perinatal outcomes associated with severe COVID-19 in pregnancy compared with those with mild and moderate COVID-19 and to explore the impact of timing of birth. MATERIAL AND METHODS: This was a secondary analysis of a national, prospective cohort study. All pregnant women admitted to hospital in the UK with symptomatic SARS-CoV-2 from March 1, 2020 to October 31, 2021 were included. The severity of maternal infection (need for high flow or invasive ventilation, intensive care admission or died), pregnancy and perinatal outcomes, and the impact of timing of birth were analyzed using multivariable logistic regression. RESULTS: Of 4436 pregnant women, 13.9% (n = 616) had severe infection. Women with severe infection were more likely to be aged ≥30 years (adjusted odds ratio [aOR] aged 30-39 1.48, 95% confidence interval [CI] 1.20-1.83), be overweight or obese (aOR 1.73, 95% CI 1.34-2.25 and aOR 2.52 95% CI 1.97-3.23, respectively), be of mixed ethnicity (aOR 1.93, 95% CI 1.17-3.21) or have gestational diabetes (aOR 1.43, 95% CI 1.09-1.87) compared with those with mild or moderate infection. Women with severe infection were more likely to have a pre-labor cesarean birth (aOR 8.84, 95% CI 6.61-11.83), a very or extreme preterm birth (28-31+ weeks' gestation, aOR 18.97, 95% CI 7.78-14.85; <28 weeks' gestation, aOR 12.35, 95% CI 6.34-24.05) and their babies were more likely to be stillborn (aOR 2.51, 95% CI 1.35-4.66) or admitted to a neonatal unit (aOR 11.61, 95% CI 9.28-14.52). Of 112 women with severe infection who were discharged and gave birth at a later admission, the majority gave birth ≥36 weeks (85.7%), noting that three women in this group (2.7%) had a stillbirth. CONCLUSIONS: Severe COVID-19 in pregnancy increases the risk of adverse outcomes. Information to promote uptake of vaccination should specifically target those at greatest risk of severe outcomes. Decisions about timing of birth should be informed by multidisciplinary team discussion; however, our data suggest that women with severe infection who do not require early delivery have mostly good outcomes but that those with severe infection at term may warrant rapid delivery.

The role of arginine, homoarginine and nitric oxide in pregnancy.

Normal pregnancy leads to profound maternal hemodynamic changes, including increased blood volume and vasodilatation. Several vasodilator mediators are implicated, including prostaglandins, carbon monoxide and nitric oxide (NO). Pre-eclampsia (PE) affects 3-10 % of pregnancies and is associated with increased maternal and perinatal morbidity and mortality. Around 8 % of pregnancies are complicated by intra-uterine growth restriction (IUGR), also associated with increased perinatal mortality and morbidity. PE and IUGR often co-exist. NO is essential for the formation of healthy endothelium, and in pregnancy promotes endovascular invasion by the cytotrophoblast. As interstitial trophoblasts invade the maternal spiral arteries in the uterine wall, they produce NO which acts on artery walls to create a low-resistance, high-caliber uteroplacental unit. If this process fails, the result is a high-resistance uteroplacental circulation. The hypoperfused and ischemic placenta releases antiangiogenic factors which mediate generalized endothelial dysfunction, oxidative stress and inflammatory mediators. It is these mediators that are implicated in both the fetal and maternal syndromes of PE and IUGR. Studies of NO and its modulator amino acids, including the precursors arginine and homoarginine and the NO synthesis inhibitor asymmetric dimethylarginine (ADMA), have investigated their role in both normal and pathological pregnancies. Many studies of PE (and, to a lesser extent, IUGR) have investigated maternal circulating ADMA, arginine and homoarginine levels. This article reviews and discusses the role of these amino acids in pregnancy. The results have shed some light on their role in these pathologies, but some of the findings have been conflicting and more research is needed. Nevertheless, therapeutic interventions that manipulate these guanidine-amino acids and their interactions hold real promise for the management of pregnancies complicated by PE and/or IUGR, and the results of ongoing studies are eagerly awaited.

Best practice recommendations for medically assisted reproduction in patients with known cardiovascular disease or at high risk of cardiovascular disease.

Increasing numbers of people are seeking assisted conception. In people with known cardiac disease or risk factors for cardiac disease, assisted conception may carry increased risks during treatment and any subsequent pregnancy. These risks should be assessed, considered and minimized prior to treatment.

Perinatal outcomes after admission with COVID-19 in pregnancy: a UK national cohort study.

There are few population-based studies of sufficient size and follow-up duration to have reliably assessed perinatal outcomes for pregnant women hospitalised with SARS-CoV-2 infection. The United Kingdom Obstetric Surveillance System (UKOSS) covers all 194 consultant-led UK maternity units and included all pregnant women admitted to hospital with an ongoing SARS-CoV-2 infection. Here we show that in this large national cohort comprising two years' active surveillance over four SARS-CoV-2 variant periods and with near complete follow-up of pregnancy outcomes for 16,627 included women, severe perinatal outcomes were more common in women with moderate to severe COVID-19, during the delta dominant period and among unvaccinated women. We provide strong evidence to recommend continuous surveillance of pregnancy outcomes in future pandemics and to continue to recommend SARS-CoV-2 vaccination in pregnancy to protect both mothers and babies.

Systematic review and meta-analysis of the effectiveness and perinatal outcomes of COVID-19 vaccination in pregnancy.

Safety and effectiveness of COVID-19 vaccines during pregnancy is a particular concern affecting vaccination uptake by this vulnerable group. Here we evaluated evidence from 23 studies including 117,552 COVID-19 vaccinated pregnant people, almost exclusively with mRNA vaccines. We show that the effectiveness of mRNA vaccination against RT-PCR confirmed SARS-CoV-2 infection 7 days after second dose was 89·5% (95% CI 69·0-96·4%, 18,828 vaccinated pregnant people, I2 = 73·9%). The risk of stillbirth was significantly lower in the vaccinated cohort by 15% (pooled OR 0·85; 95% CI 0·73-0·99, 66,067 vaccinated vs. 424,624 unvaccinated, I2 = 93·9%). There was no evidence of a higher risk of adverse outcomes including miscarriage, earlier gestation at birth, placental abruption, pulmonary embolism, postpartum haemorrhage, maternal death, intensive care unit admission, lower birthweight Z-score, or neonatal intensive care unit admission (p > 0.05 for all). COVID-19 mRNA vaccination in pregnancy appears to be safe and is associated with a reduction in stillbirth.

Efficacy of carbetocin in the prevention of postpartum hemorrhage: a systematic review and Bayesian meta-analysis of randomized trials.

OBJECTIVES: To evaluate the efficacy of carbetocin for the prevention of postpartum hemorrhage (PPH) and related events after vaginal or cesarean delivery. METHODS: Medline, Scopus, Embase, and the Cochrane Library were searched in February 2018 using combinations of the relevant MeSH terms, keywords. Randomized studies, comparing carbetocin to any other uterotonic agent, in the management of cesarean and vaginal deliveries, were conducted. Two reviewers independently extracted the data. A random-effects meta-analysis was used for quantitative synthesis. Also, Bayesian random-effect metaregression was used to estimate the posterior probabilities (PP) for benefits of carbetocin use. RESULTS: After the full-text review, 30 trials were included in the meta-analysis. Compared to oxytocin, carbetocin was associated with a reduced need for additional uterotonic use in women undergoing cesarean delivery (RR 0.43, 95% CI 0.30-0.59, I2 = 71%, 3216 women, PP > 99.9%). Women at high risk of PPH delivering vaginally also had a reduced need for additional uterotonic use with carbetocin compared to oxytocin (RR 0.56, 95% CI 0.34-0.94, I2 = 38%, 789 women, PP = 81.2%). The risk of postpartum blood transfusion (RR 0.57, 95% CI 0.33-0.96, I2 = 0%, 1991 women, PP = 97.9%) was also less with carbetocin compared to oxytocin in high-risk women undergoing cesarean delivery. The risk of PPH was similar between carbetocin and other uterotonic agents for both cesarean (RR 0.69, 95% CI 0.45-1.05, I2 = 27%, 2926 women, PP = 96.3%) and vaginal deliveries (RR 0.61, 95% CI 0.32-1.14, I2 = 35%, 1515 women, PP = 88.9%). CONCLUSIONS: Carbetocin is effective in reducing the need for additional uterotonic use and postpartum blood transfusion in women at increased risk of PPH undergoing cesarean delivery. There is still a need for high-quality trials on its effectiveness in preventing PPH in high-risk women.PrecisCarbetocin is effective in reducing the need for additional uterotonic use and postpartum blood transfusion in high-risk women undergoing Cesarean delivery.

Global changes in maternity care provision during the COVID-19 pandemic: A systematic review and meta-analysis.

BACKGROUND: The COVID-19 pandemic has had a profound impact on healthcare systems globally, with a worrying increase in adverse maternal and foetal outcomes. We aimed to assess the changes in maternity healthcare provision and healthcare-seeking by pregnant women during the COVID-19 pandemic. METHODS: We performed a systematic review and meta-analysis of studies of the effects of the pandemic on provision of, access to and attendance at maternity services (CRD42020211753). We searched MEDLINE and Embase in accordance with PRISMA guidelines from January 1st, 2020 to April 17th 2021 for controlled observational studies and research letters reporting primary data comparing maternity healthcare-seeking and healthcare delivery during compared to before the COVID-19 pandemic. Case reports and series, systematic literature reviews, and pre-print studies were excluded. Meta-analysis was performed on comparable outcomes that were reported in two or more studies. Data were combined using random-effects meta-analysis, using risk ratios (RR) or incidence rate ratios (IRR) with 95% confidence intervals (CI). FINDINGS: Of 4743 citations identified, 56 were included in the systematic review, and 21 in the meta-analysis. We identified a significant decrease in the number of antenatal clinic visits (IRR 0614, 95% CI 0486-0776, P<00001, I2=54.6%) and unscheduled care visits (IRR 0741, 95% CI 0602-0911, P = 00046, I2=00%) per week, and an increase in virtual or remote antenatal care (IRR 4656 95% CI 7762-2794, P<00001, I2=90.6%) and hospitalisation of unscheduled attendees (RR 1214, 95% CI 1118-1319, P<00001, I2=00%). There was a decrease in the use of GA for category 1 Caesarean sections (CS) (RR 0529, 95% CI 0407-0690, P<00001, I2=00%). There was no significant change in intrapartum epidural use (P = 00896) or the use of GA for elective CS (P = 079). INTERPRETATION: Reduced maternity healthcare-seeking and healthcare provision during the COVID-19 pandemic has been global, and must be considered as potentially contributing to worsening of pregnancy outcomes observed during the pandemic.

Effects of the COVID-19 pandemic on maternal and perinatal outcomes: a systematic review and meta-analysis.

BACKGROUND: The COVID-19 pandemic has had a profound impact on health-care systems and potentially on pregnancy outcomes, but no systematic synthesis of evidence of this effect has been undertaken. We aimed to assess the collective evidence on the effects on maternal, fetal, and neonatal outcomes of the pandemic. METHODS: We did a systematic review and meta-analysis of studies on the effects of the pandemic on maternal, fetal, and neonatal outcomes. We searched MEDLINE and Embase in accordance with PRISMA guidelines, from Jan 1, 2020, to Jan 8, 2021, for case-control studies, cohort studies, and brief reports comparing maternal and perinatal mortality, maternal morbidity, pregnancy complications, and intrapartum and neonatal outcomes before and during the pandemic. We also planned to record any additional maternal and offspring outcomes identified. Studies of solely SARS-CoV-2-infected pregnant individuals, as well as case reports, studies without comparison groups, narrative or systematic literature reviews, preprints, and studies reporting on overlapping populations were excluded. Quantitative meta-analysis was done for an outcome when more than one study presented relevant data. Random-effects estimate of the pooled odds ratio (OR) of each outcome were generated with use of the Mantel-Haenszel method. This review was registered with PROSPERO (CRD42020211753). FINDINGS: The search identified 3592 citations, of which 40 studies were included. We identified significant increases in stillbirth (pooled OR 1·28 [95% CI 1·07-1·54]; I2=63%; 12 studies, 168 295 pregnancies during and 198 993 before the pandemic) and maternal death (1·37 [1·22-1·53; I2=0%, two studies [both from low-income and middle-income countries], 1 237 018 and 2 224 859 pregnancies) during versus before the pandemic. Preterm births before 37 weeks' gestation were not significantly changed overall (0·94 [0·87-1·02]; I2=75%; 15 studies, 170 640 and 656 423 pregnancies) but were decreased in high-income countries (0·91 [0·84-0·99]; I2=63%; 12 studies, 159 987 and 635 118 pregnancies), where spontaneous preterm birth was also decreased (0·81 [0·67-0·97]; two studies, 4204 and 6818 pregnancies). Mean Edinburgh Postnatal Depression Scale scores were higher, indicating poorer mental health, during versus before the pandemic (pooled mean difference 0·42 [95% CI 0·02-0·81; three studies, 2330 and 6517 pregnancies). Surgically managed ectopic pregnancies were increased during the pandemic (OR 5·81 [2·16-15·6]; I2=26%; three studies, 37 and 272 pregnancies). No overall significant effects were identified for other outcomes included in the quantitative analysis: maternal gestational diabetes; hypertensive disorders of pregnancy; preterm birth before 34 weeks', 32 weeks', or 28 weeks' gestation; iatrogenic preterm birth; labour induction; modes of delivery (spontaneous vaginal delivery, caesarean section, or instrumental delivery); post-partum haemorrhage; neonatal death; low birthweight (<2500 g); neonatal intensive care unit admission; or Apgar score less than 7 at 5 min. INTERPRETATION: Global maternal and fetal outcomes have worsened during the COVID-19 pandemic, with an increase in maternal deaths, stillbirth, ruptured ectopic pregnancies, and maternal depression. Some outcomes show considerable disparity between high-resource and low-resource settings. There is an urgent need to prioritise safe, accessible, and equitable maternity care within the strategic response to this pandemic and in future health crises. FUNDING: None.

SARS-CoV-2 infection in pregnancy: A systematic review and meta-analysis of clinical features and pregnancy outcomes.

BACKGROUND: Perform a systematic review and meta-analysis of SARS-CoV-2 infection and pregnancy. METHODS: Databases (Medline, Embase, Clinicaltrials.gov, Cochrane Library) were searched electronically on 6th April and updated regularly until 8th June 2020. Reports of pregnant women with reverse transcription PCR (RT-PCR) confirmed COVID-19 were included. Meta-analytical proportion summaries and meta-regression analyses for key clinical outcomes are provided. FINDINGS: 86 studies were included, 17 studies (2567 pregnancies) in the quantitative synthesis; other small case series and case reports were used to extract rarely-reported events and outcome. Most women (73.9%) were in the third trimester; 52.4% have delivered, half by caesarean section (48.3%). The proportion of Black, Asian or minority ethnic group membership (50.8%); obesity (38.2%), and chronic co-morbidities (32.5%) were high. The most commonly reported clinical symptoms were fever (63.3%), cough (71.4%) and dyspnoea (34.4%). The commonest laboratory abnormalities were raised CRP or procalcitonin (54.0%), lymphopenia (34.2%) and elevated transaminases (16.0%). Preterm birth before 37 weeks' gestation was common (21.8%), usually medically-indicated (18.4%). Maternal intensive care unit admission was required in 7.0%, with intubation in 3.4%. Maternal mortality was uncommon (~1%). Maternal intensive care admission was higher in cohorts with higher rates of co-morbidities (beta=0.007, p<0.05) and maternal age over 35 years (beta=0.007, p<0.01). Maternal mortality was higher in cohorts with higher rates of antiviral drug use (beta=0.03, p<0.001), likely due to residual confounding. Neonatal nasopharyngeal swab RT-PCR was positive in 1.4%. INTERPRETATION: The risk of iatrogenic preterm birth and caesarean delivery was increased. The available evidence is reassuring, suggesting that maternal morbidity is similar to that of women of reproductive age. Vertical transmission of the virus probably occurs, albeit in a small proportion of cases. FUNDING: N/A.