A new study from the University of Texas (UT) Southwestern has found that pregnant women who test positive for the coronavirus disease 2019 (COVID-19) and their newborn babies have a low risk of developing severe symptoms.

The study showed that 95% of women who tested positive for COVID-19 during pregnancy had no adverse outcomes, with the virus being transmitted to the fetus in just 3% of the cases.

“Our findings are that approximately 5% of all delivered women with COVID-19 infection develop severe or critical illness. Five percent is a major concern when a pandemic is making its way through a population; however, it’s lower than previous reports from the Centers for Disease Control and Prevention (CDC),” said study author Emily Adhikari, MD, in a prepared statement. “Most women with asymptomatic or mild infection will be relieved to know that their babies are unlikely to be affected by the virus.”

The objective of the study was to measure how COVID-19 infection impacts pregnancy outcomes and how severe disease could be in pregnant women, as well as impacts on placental pathology and neonatal infections, by studying women at Parkland Health and Hospital System, a prenatal clinic affiliated with UT Southwestern.

The researchers followed 3374 mothers, 252 of whom tested positive for the virus during pregnancy, from March through August. The group was predominantly Hispanic (75%), followed by Black (18%), and white (4%). There were no significant differences between the expectant mothers in age, number of previous births, body mass index, or diabetes, according to the study authors. 

Among the 252 women who tested positive, 95% were asymptomatic or had mild symptoms at first. Additionally, 6 of those women developed severe or critical COVID-19 pneumonia. When comparing mothers with and without COVID-19 diagnosed any time during pregnancy, the virus did not increase the risk of adverse outcomes, including preterm birth, preeclampsia with severe features, or cesarean delivery for abnormal fetal heart rate. However, preterm birth was increased among mothers who developed severe or critical illness before reaching 37 weeks in their pregnancy. Further the study found that diabetes may be a factor that increases the risk for severe or critical maternal illness.

The pathologists who examined placentas found that the majority were unaffected by the virus, according to the study authors.

Mothers with COVID-19 who were outpatients were followed using telemedicine with a scripted evaluation of symptoms and protocol-based management, including instructions for referral to the emergency department for worsening respiratory symptoms or obstetric concerns.

The study authors noted that further study is needed to understand whether maternal infection with COVID-19 impacts long-term maternal or infant health.

“Our goal is to develop evidence-based guidelines for the majority of pregnant women who are recovering at home,” Adhikari said in a prepared statement. “It’s difficult to predict who will become severely ill, which is why prevention strategies such as hand-washing, masking, and social distancing are still extremely important.”

REFERENCE
Study finds low risk of pregnancy complications from COVID-19. UT Southwestern Medical Center. Published November 19, 2020. Accessed November 24, 2020. https://www.utsouthwestern.edu/newsroom/articles/year-2020/low-risk-pregnancy-complications-covid.html#:~:text=DALLAS%20%E2%80%93%20Nov.%2019%2C%202020,new%20study%20from%20UT%20Southwestern