Jan 19, 2022 -- Two new studies show how COVID-19 threatens the health of pregnant people and their newborn infants.

A study conducted in Scotland showed that unvaccinated pregnant people who got COVID were much more likely to have a stillborn infant or one that dies in the first 28 days. The study also found that pregnant women infected with COVID died and needed hospitalization at a much higher rate than vaccinated women who got pregnant.

The University of Edinburgh and Public Health Scotland studied national data in 88,000 pregnancies between December 2020 and October 2021, according to the study published in Nature Medicine.

Overall, 77.4% of infections, 90.9% of COVID-related hospitalizations, and 98% of critical care cases occurred in the unvaccinated people, as did all newborn deaths.

The study said 2,364 babies were born to women infected with COVID, with 2,353 live births. Eleven babies were stillborn and eight live-born babies died within 28 days. Of the live births, 241 were premature.

The problems were more likely if the infection occurred 28 days or less before the delivery date, the researchers said.

The authors said the low vaccination rate among pregnant people was a problem. Only 32% of people giving birth in October 2021 were fully vaccinated, while 77% of the Scottish female population aged 18-44 was fully vaccinated.

"Vaccine hesitancy in pregnancy thus requires addressing, especially in light of new recommendations for booster vaccination administration 3 months after the initial vaccination course to help protect against new variants such as Omicron," the authors wrote. "Addressing low vaccine uptake rates in pregnant women is imperative to protect the health of women and babies in the ongoing pandemic."

Vaccinated women who were pregnant had complication rates that were about the same for all pregnant women, the study shows.

The second study, published in Lancet, found that women who got COVID while pregnant in five Western U.S. states were more likely to have premature births, low birth weights, and stillbirths, even when the COVID cases are mild.

The Institute for Systems Biology researchers in Seattle studied data for women who gave birth in Alaska, California, Montana, Oregon, or Washington from March 5, 2020, to July 4, 2021. About 18,000 of them were tested for COVID, with 882 testing positive. Of the positive tests, 85 came in the first trimester, 226 in the second trimester, and 571 in the third semester. None of the pregnant women had been vaccinated at the time they were infected.

Most of the birth problems occurred with first and second trimester infections, the study noted, and problems occurred even if the pregnant person didn’t have respiratory complications, a major COVID symptom.

“Pregnant people are at an increased risk of adverse outcomes following SARS-CoV-2 infection, even when maternal COVID-19 is less severe, and they may benefit from increased monitoring following infection,” Jennifer Hadlock, MD, an author of the paper, said in a news release.

The study also pointed out continuing inequities in health care, with most of the positive cases occurring among young, non-white people with Medicaid and high body mass index.

Show Sources

Nature. “SARS-CoV-2 infection and COVID-19 vaccination rates in pregnant women in Scotland”

Lancet. “The effect of maternal SARS-CoV-2 infection timing on birth outcomes: a retrospective multicentre cohort study”

Institute for Systems Biology. “Maternal COVID-19 infection increases risks of preterm birth, low birth weight and stillbirth

© 2022 WebMD, LLC. All rights reserved. View privacy policy and trust info