International Registry of Coronavirus Exposure in Pregnancy (IRCEP): Cohort Description and Methodological Considerations

Association Between COVID-19 During Pregnancy and Preterm Birth by Trimester of Infection: A Retrospective Cohort Study Using Longitudinal Social Media Data

Background

Preterm birth, defined as birth at <37 weeks of gestation, is the leading cause of neonatal death globally and, together with low birthweight, the second leading cause of infant mortality in the United States. There is mounting evidence that COVID-19 infection during pregnancy is associated with an increased risk of preterm birth; however, data remain limited by trimester of infection. The ability to study COVID-19 infection during the earlier stages of pregnancy has been limited by available sources of data. The objective of this study was to use self-reports in large-scale, longitudinal social media data to assess the association between trimester of COVID-19 infection and preterm birth.

Methods

In this retrospective cohort study, we used natural language processing and machine learning, followed by manual validation, to identify pregnant Twitter users and to search their longitudinal collection of publicly available tweets for reports of COVID-19 infection during pregnancy and, subsequently, a preterm birth or term birth (i.e., a gestational age ≥37 weeks) outcome. Among the users who reported their pregnancy on Twitter, we also identified a 1:1 age-matched control group, consisting of users with a due date prior to January 1, 2020-that is, without COVID-19 infection during pregnancy. We calculated the odds ratios (ORs) with 95% confidence intervals (CIs) to compare the overall rates of preterm birth for pregnancies with and without COVID-19 infection and by timing of infection: first trimester (weeks 1-13), second trimester (weeks 14-27), or third trimester (weeks 28-36).

Results

Through August 2022, we identified 298 Twitter users who reported COVID-19 infection during pregnancy, a preterm birth or term birth outcome, and maternal age: 94 (31.5%) with first-trimester infection, 110 (36.9%) second-trimester infection, and 95 (31.9%) third-trimester infection. In total, 26 (8.8%) of these 298 users reported preterm birth: 8 (8.5%) were infected during the first trimester, 7 (6.4%) were infected during the second trimester, and 12 (12.6%) were infected during the third trimester. In the 1:1 age-matched control group, 13 (4.4%) of the 298 users reported preterm birth. Overall, the risk of preterm birth was significantly higher for pregnancies with COVID-19 infection compared to those without (OR 2.1, 95% CI 1.06-4.16). In particular, the risk of preterm birth was significantly higher for pregnancies with COVID-19 infection during the third trimester (OR 3.17, CI 1.39-7.21).

Conclusion

The results of our study suggest that COVID-19 infection particularly during the third trimester is associated with an increased risk of preterm birth.

The COVID-19 Vaccines International Pregnancy Exposure Registry (C-VIPER): Protocol and Methodological Considerations

INTRODUCTION

The advent of the coronavirus disease 2019 (COVID-19) pandemic has led to the development of vaccines against severe acute respiratory syndrome coronavirus 2. Prospective evidence regarding safety for pregnant people and their developing fetuses is lacking. The aim of the COVID-19 Vaccines International Pregnancy Exposure Registry (C-VIPER) is to estimate the relative risk of obstetric, neonatal, and infant outcomes by comparing participants vaccinated against COVID-19 during pregnancy to a reference group of people enrolled in the Pregistry International Pregnancy Exposure Registry (PIPER) who remained unvaccinated during pregnancy.

METHODS

The C-VIPER and the PIPER are international, non-interventional, real-world cohort studies. Participants receiving a COVID-19 vaccine during pregnancy will be matched in the analyses by country and gestational age at enrollment to unvaccinated individuals. Self-enrolled and self-consented participants complete online questionnaires at enrollment, during pregnancy, and for 12 months after the delivery of a live infant. Where possible, outcomes are verified by medical records. The study aims to recruit at least 500 pregnancies for each approved or authorized vaccine and will last for 5 years for each product.

CONCLUSIONS

By collecting data for each vaccine brand, the C-VIPER will be able to determine individual safety profiles. The study design allows for analysis of the effects of exposure to COVID-19 vaccines during specific etiologically relevant periods of gestation. Although the sample size may be too small to detect associations with rare outcomes, the study will be used to generate hypotheses for future research. Ultimately, the C-VIPER should provide data that will allow pregnant people and their healthcare providers to make informed decisions about COVID-19 vaccination.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT04705116. Registered on 12 January, 2021. EU PAS EUPAS39096. Registered on 20 January, 2021.

Social determinants of health associated with COVID-19 severity during pregnancy: a multinational cohort study (in the International Registry of Coronavirus Exposure in Pregnancy)

BACKGROUND

The COVID-19 pandemic has caused morbidity and mortality, particularly among vulnerable populations. We aimed to assess social and demographic characteristics associated with COVID-19 severity among symptomatic participants during pregnancy.

METHODS

The International Registry of Coronavirus Exposure in Pregnancy is a multinational, longitudinal observational cohort study of adult participants tested for SARS-CoV-2 or who received clinical diagnosis of COVID-19 during pregnancy (NCT04366986). Disease severity status of mild, moderate, or severe was determined based on symptoms and healthcare utilization. Stratified by current versus recent pregnancy at enrollment, univariate mixed-effects logistic regression modeling was used to characterize association between social and demographic characteristics with COVID-19 severity, using a cumulative mixed effect model with country as a random effect.

RESULTS

The odds of developing more severe COVID-19 (odds ratio [95% confidence interval]) were higher among participants with lower socioeconomic status (poor: 2.72 [2.01,3.69]; lower-middle class: 2.07 [1.62,2.65] vs wealthy), among participants with lower educational attainment (high school: 1.68 [1.39,2.03]; < high school (1.77 [1.25,2.51] vs graduate education). Participants over 25 years of age had lower odds of severe COVID-19 versus participants < 25 years (25-34: 0.69 [0.56,0.85]; 35-50: 0.62 [0.48,0.80]). Employment in food services was also associated with increased odds of more severe COVID-19, whereas employment in healthcare and within home, and primiparity were associated with lower severity.

CONCLUSIONS

Findings suggest that employment setting and economic status have strong associations with COVID-19 severity, which warrants considering social determinants of health in the context of assessing risk factors of more severe COVID-19 during pregnancy.

TRIAL REGISTRATION

IRCEP was registered with the European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (ENCePP) [EUPAS37360] and clinicaltrials.gov [NCT04366986].

Timing and severity of COVID-19 during pregnancy and risk of preterm birth in the International Registry of Coronavirus Exposure in Pregnancy

Background

Studies of preterm delivery after COVID-19 are often subject to selection bias and do not distinguish between early vs. late infection in pregnancy, nor between spontaneous vs. medically indicated preterm delivery. This study aimed to estimate the risk of preterm birth (overall, spontaneous, and indicated) after COVID-19 during pregnancy, while considering different levels of disease severity and timing.

Methods

Pregnant and recently pregnant people who were tested for or clinically diagnosed with COVID-19 during pregnancy enrolled in an international internet-based cohort study between June 2020 and July 2021. We used several analytic approaches to minimize confounding and immortal time bias, including multivariable regression, time-to-delivery models, and a case-time-control design.

Results

Among 14,264 eligible participants from 70 countries who did not report a pregnancy loss before 20 gestational weeks, 5893 had completed their pregnancies and reported delivery information; others were censored at time of their last follow-up. Participants with symptomatic COVID-19 before 20 weeks’ gestation had no increased risk of preterm delivery compared to those testing negative, with adjusted risks of 10.0% (95% CI 7.8, 12.0) vs. 9.8% (9.1, 10.5). Mild COVID-19 later in pregnancy was not clearly associated with preterm delivery. In contrast, severe COVID-19 after 20 weeks’ gestation led to an increase in preterm delivery compared to milder disease. For example, the risk ratio for preterm delivery comparing severe to mild/moderate COVID-19 at 35 weeks was 2.8 (2.0, 4.0); corresponding risk ratios for indicated and spontaneous preterm delivery were 3.7 (2.0, 7.0) and 2.3 (1.2, 3.9), respectively.

Conclusions

Severe COVID-19 late in pregnancy sharply increased the risk of preterm delivery compared to no COVID-19. This elevated risk was primarily due to an increase in medically indicated preterm deliveries, included preterm cesarean sections, although an increase in spontaneous preterm delivery was also observed. In contrast, mild or moderate COVID-19 conferred minimal risk, as did severe disease early in pregnancy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-05101-3.

First trimester COVID-19 and the risk of major congenital malformations-International Registry of Coronavirus Exposure in Pregnancy

There is limited information about the effects of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection during the first trimester of pregnancy on the risk of major congenital malformations (MCMs). The International Registry of Coronavirus Exposure in Pregnancy (IRCEP) was designed to estimate the relative risk of adverse perinatal outcomes among women with Coronavirus Disease 2019 (COVID‐19) at specific times during gestation. Adult women were eligible to enroll if they had a SARS‐CoV‐2 test, regardless of the results, or clinically confirmed COVID‐19 during pregnancy. Self‐administered questionnaires collected data on SARS‐CoV‐2 infection, pregnancy outcomes (including detailed questions on MCMs), and potential confounders. The analysis of MCMs includes women with either a positive SARS‐CoV‐2 PCR test or a clinical diagnosis of COVID‐19 during the first trimester (exposed group) or a negative SARS‐CoV‐2 test (reference) that enrolled while pregnant. Sensitivity analyses were restricted to participants who enrolled before the availability of informative prenatal screening tests and extended to those enrolled after end of pregnancy. Generalized linear models were used to estimate relative risks (RR) and 95% confidence intervals (CI). Of 17,163 participants enrolled between June 2020 and July 2021, 1727 had a SARS‐CoV‐2 infection during the first trimester, of whom 1,675 enrolled during pregnancy. Of 10,235 controls with a negative test during pregnancy, 4,172 enrolled during pregnancy. Restriction to participants with complete follow‐up reduced the sample size to 92 exposed and 292 unexposed reference pregnancies. MCMs were reported in 3 (3.3%) exposed and 8 (2.7%) unexposed (RR 1.2; 95% CI 0.32–4.2) newborns. The RR was 2.5 (95%CI 0.23–27) among those enrolled before prenatal screening, and 2.2 (95%CI 0.89–5.3) in the overall study population including those enrolled post‐pregnancy. No specific pattern of malformations was observed. Although results are compatible with no major teratogenic effects associated with maternal SARS‐CoV‐2 infection, RR estimates were imprecise and larger studies are warranted.

COVID ‐19 pharmacotherapy utilization patterns during pregnancy: International Registry of Coronavirus Exposure in Pregnancy ( IRCEP )

Purpose

Women infected with SARS‐CoV‐2 during pregnancy are at increased risk of developing severe illness and experience a higher rate of preterm births than pregnant women who are not infected. The use of innovative or repurposed therapies to treat COVID‐19 patients is widespread; however, there are very limited data regarding the patterns of use and safety profile of most of these therapeutics in pregnant women. We assessed the patterns of use of COVID‐19 therapeutics during pregnancy using data from the International Registry of Coronavirus in Pregnancy (IRCEP).

Methods

The IRCEP is an international observational cohort study intended to assess the risk of major obstetric and neonatal outcomes among pregnant women with COVID‐19. Women enrolled while pregnant or within 6 months after end of pregnancy. Follow‐up for women enrolled while pregnant includes monthly online questionnaires throughout the pregnancy and, for live births, through the infant's first 90 days of life. Participants provide information on demographic characteristics, health history, COVID‐19 tests and symptoms, medications, and obstetric and neonatal outcomes.

Results

A total of 5780 women with COVID‐19 during pregnancy were identified from the IRCEP. Severity of COVID‐19 was classified in 372 of them as severe, 3053 moderate, and 2355 mild. The most frequently reported COVID‐19 therapies, other than analgesics, included azithromycin (12.8%), steroids (3.5%), interferon (2.4%), oseltamivir (2.1%), chloroquine/hydroxychloroquine (1.7%), anticoagulants (2.0%), antibodies (0.9%), and remdesivir (0.3%). Most drugs were preferentially used for severe cases. Patterns of use varied by country.

Conclusions

IRCEP participants reported use of therapeutics for COVID‐19 during pregnancy for which there is little safety information. Findings on COVID‐19 pharmacotherapy utilization patterns can guide future studies examining the safety of COVID‐19 therapies during pregnancy.

Association between SARS-CoV-2 infection during pregnancy and postpartum depressive and anxiety symptoms: finding from the International Registry of Coronavirus Exposure in Pregnancy (IRCEP) study

While there has been concern over the perinatal mental health implications of the COVID-19 outbreak, evidence on the risk of postpartum depression and anxiety following SARS-CoV-2 infection is limited. We studied this question using the International Registry of Coronavirus Exposure in Pregnancy, which included both a prospective and retrospective cohort. Study participants were required to have been tested for SARS-CoV-2 between the date of last menstrual period and delivery. The exposure of interest was SARS-CoV-2 infection during pregnancy, as well as COVID-19 severity (severe, moderate, mild, and asymptomatic). The outcome was postpartum depression and anxiety symptoms, assessed by the 4-item Patient Health Questionnaire. The final analytic cohort consisted of 3819 participants (COVID-19 positive: 771; COVID-19 negative: 3048). After adjusting for confounding by socio-demographics, prior obstetric and maternal health comorbidities, mothers with severe COVID-19 had an increased risk of depressive (aRR: 1.72; 95%CI: 1.18-2.52) and anxiety (aRR: 1.40; 0.98-2.00) symptoms. The strength of the association was attenuated for women with moderate COVID-19 (aRR = 1.12; 0.86-1.44 for depressive symptoms; aRR = 1.18; 0.96-1.44 for anxiety symptoms). No increased risk was observed for mild or asymptomatic illness. The findings can inform targeted interventions to minimize the risk of adverse COVID-19-related mental health outcomes for pregnant women.