Unvaccinated pregnant women infected with coronavirus have more than twice the risk of having dangerous sepsis or other severe medical problems, than those who don’t have the virus, according to a study of thousands of northern California women.
This latest research adds to the body of research showing the risks faced by pregnant women due to COVID-19, especially among those who are not vaccinated.
The analysis of 43,886 women who gave birth at Kaiser Permanente Northern California between 1 March 2020, and 16 March 2021 — before coronavirus vaccines were widely available — revealed that babies born to mothers who contracted COVID were also more likely to be born prematurely, placing them at greater risk for brain and heart problems, reports the San Francisco Chronicle.
The negative outcomes for pregnant people with COVID-19 ranged from preterm birth and blood clots to respiratory distress syndrome and sepsis, according to researchers with Kaiser Permanente, a healthcare system, who analysed the data of more than 43,000 pregnant people during the first year of the coronavirus pandemic.
“These findings add to the growing evidence that having COVID-19 during pregnancy raises risks of serious complications,” said the study’s lead author, Dr Assiamira Ferrara, a senior research scientist and associate director of the women’s and children’s health section in the Kaiser Permanente Division of Research.
“Coupled with the evidence that the COVID-19 vaccines are safe during pregnancy, these findings should aid patients in understanding the risks of perinatal complications and the need for vaccination.” The research was published in JAMA Internal Medicine.
Earlier this year, another study published in Nature Medicine found that unvaccinated pregnant people with COVID-19 and their newborn babies have a higher risk of complications from the disease, like hospitalisations and newborn deaths, compared to those who are vaccinated against the virus.
The study, reports ABC News, led by researchers in Scotland, found that unvaccinated pregnant people who contracted COVID not only had a risk of more severe illness themselves, but also were more likely to experience pregnancy loss or preterm birth compared to other women, leading the researchers to conclude: “Addressing low vaccine uptake in pregnant women is imperative to protect the health of women and babies.”
In the United States, as of mid-March, just more than 60% of all pregnant people ages 18-49 had been fully vaccinated, prior to or during pregnancy.
Study details
Perinatal Complications in Individuals in California With or Without SARS-CoV-2 Infection During Pregnancy
Assiamira Ferrara, Monique Hedderson, Yeyi Zhu, et al
Published in JAMA on 22 March 2022
Key Points
Question What is the risk of perinatal complications associated with SARS-CoV-2 infection during pregnancy and what factors are associated with hospitalisations?
Findings In this cohort study of 43,886 pregnant women, SARS-CoV-2 infection during pregnancy was associated with an increased risk of severe maternal morbidity, preterm birth, and venous thromboembolism. Pregestational diabetes and Asian or Pacific Islander and black race and ethnicity were associated with an increased risk of hospitalisation.
Meaning This study found that SARS-CoV-2 infection may be associated with an increased risk of perinatal complications; this information can help inform treatment of the infection during pregnancy, aid patients in understanding the risks of these complications, and support the recommendation for vaccination of pregnant individuals and those planning conception.
Abstract
Importance Additional research from population-based studies is needed to inform the treatment of SARS-CoV-2 infection during pregnancy and to provide health risk information to pregnant individuals.
Objective To assess the risk of perinatal complications associated with SARS-CoV-2 infection and to describe factors associated with hospitalisations.
Design, Setting, and Participants This population-based cohort study included 43,886 pregnant individuals with longitudinal electronic health record data from preconception to delivery who delivered at Kaiser Permanente Northern California between March 1, 2020, and March 16, 2021. Individuals with diagnostic codes for COVID-19 that did not have a confirmatory polymerase chain reaction test for SARS-CoV-2 were excluded.
Exposures SARS-CoV-2 infection detected by polymerase chain reaction test (from 30 days before conception to 7 days after delivery) as a time varying exposure.
Main Outcomes and Measures Severe maternal morbidity including 21 conditions (eg, acute myocardial infarction, acute renal failure, acute respiratory distress syndrome, and sepsis) that occurred at any time during pregnancy or delivery; preterm birth; pregnancy hypertensive disorders; gestational diabetes; venous thromboembolism (VTE); stillbirth; cesarean delivery; and newborn birth weight and respiratory conditions. Standardised mean differences between individuals with and without SARS-CoV-2 were calculated. Cox proportional hazards regression was used to estimate the hazard ratios (HRs) and 95% CIs for the association between SARS-CoV-2 infection and perinatal complications and hospitalisation and to consider the timing of SARS-CoV-2 infection relative to outcomes.
Results
In this study of 43 886 pregnant individuals (mean [SD] age, 30.7 [5.2] years), individuals with a SARS-CoV-2 infection (1332 [3.0%]) were more likely to be younger, Hispanic, multiparous individuals with a higher neighbourhood deprivation index and obesity or chronic hypertension. After adjusting for demographic characteristics, comorbidities, and smoking status, individuals with SARS-CoV-2 infection had higher risk for severe maternal morbidity (HR, 2.45; 95% CI, 1.91-3.13), preterm birth (<37 weeks; HR, 2.08; 95% CI, 1.75-2.47), and VTE (HR, 3.08; 95% CI, 1.09-8.74) than individuals without SARS-CoV-2. SARS-CoV-2 infection was also associated with increased risk of medically indicated preterm birth (HR, 2.56; 95% CI, 2.06-3.19); spontaneous preterm birth (HR, 1.61; 95% CI, 1.22-2.13); and early (HR, 2.52; 95% CI, 1.49-4.24), moderate (HR, 2.18; 95% CI, 1.25-3.80), and late (HR, 1.95; 95% CI, 1.61-2.37) preterm birth. Among individuals with SARS-CoV-2 infection, 76 (5.7%) had a hospitalisation; pregestational diabetes (HR, 7.03; 95% CI, 2.22-22.2) and Asian or Pacific Islander (HR, 2.33; 95% CI, 1.06-5.11) and Black (HR, 3.14; 95% CI, 1.24-7.93) race and ethnicity were associated with an increased risk of hospitalisation.
Conclusions and Relevance
In this cohort study, SARS-CoV-2 infection was associated with increased risk of severe maternal morbidity, preterm birth, and VTE. The study findings inform clinicians and patients about the risk of perinatal complications associated with SARS-CoV-2 infection in pregnancy and support vaccination of pregnant individuals and those planning conception.
ABC News article – COVID-19 may double severe complications in pregnancy, study finds (Open access)
See more from MedicalBrief archives:
Maternal COVID infection increases preterm/low birth/stillbirth rate in unvaccinated women
COVID in late pregnancy linked to more complications – University of Edinburgh
COVID vaccination not linked to premature birth or unusually small babies – CDC study
COVID increases pregnancy and birth complications — French hospital study
Delta variant increases COVID-19 risks for pregnant women
Pandemic linked to substantially worse pregnancy outcomes worldwide