Delta variant increases risk of adverse outcomes in pregnant women, new UAB study shows

New study from UAB women’s health, infectious diseases and pediatric experts show increase in morbidity and adverse outcomes in pregnant patients caused by the Delta variant.

Editor's Note: The information published in this story is accurate at the time of publication. Always refer to uab.edu/uabunited for UAB's current guidelines and recommendations relating to COVID-19.



Pregnant woman with protective face mask laying sick at home.New study from UAB women’s health, infectious diseases and pediatric experts show increase in morbidity and adverse outcomes in pregnant patients caused by the Delta variant. Pregnant women have been a population of concern for physicians since the beginning of the COVID-19 pandemic. The National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network reported early on that the frequency of cesarean delivery, preterm birth and pregnancy-related hypertension were increased in pregnant women who developed severe or critical illness from the novel coronavirus.

Physicians at the University of Alabama at Birmingham Hospital and their pregnant patients let out a small sigh of relief in May and June of 2021 as cases and hospitalizations hit some of the lowest numbers since the beginning of the pandemic. However, the highly transmissible Delta variant soon became the dominant strain and caused a rise in cases, hospitalizations and deaths across Alabama. The surge included a seemingly higher number of pregnant patients with COVID-19 in hospitals and intensive care units than in previous surges. 

“We saw an alarming increase in pregnant patients hospitalized with the Delta variant in July and August,” said Akila Subramaniam, M.D., associate professor in UAB’s Division of Maternal-Fetal Medicine. “Even more, many of our patients were delivering pre-term because of the effects of the virus on these women.” 

Watch UAB women’s health and infectious diseases doctors discuss the Delta variant, vaccines and pregnancy here.

Researchers tracked admission rates and maternal and neonatal outcomes of pregnant COVID-19 patients at UAB Hospital from March 22, 2020, to Aug. 18, 2021. Outcomes were compared between pre-Delta and Delta groups. Early findings from the study showed serious morbidity and adverse outcomes associated with the Delta variant and pregnancy. 

Prior to the Delta variant, UAB Hospital saw the highest admission of pregnant women with active COVID-19 in July 2020. A total of 28 pregnant patients were admitted that month, three of whom were admitted to the intensive care unit. In comparison, 39 pregnant patients, with 11 in the intensive care unit, were hospitalized in just the first 18 days of August. 

UAB Women and Infants CenterUAB Women and Infants Center
(Photography: Steve Wood)
“Pregnant women are a high-risk population with low-vaccination rates overall,” said Jodie Dionne, M.D., associate director of UAB Global Health in the Center for Women’s Reproductive Health and associate professor in the Division of Infectious Diseases. “There is misinformation circulating that causes doubt in the vaccines or downplays the effect of the virus. This study highlights how dangerous contracting the virus, especially the Delta variant, can be for the mom and baby.” 

From the study’s early findings, the UAB researchers emphasize recommendations from the Society of Maternal-Fetal Medicine, the American College of Obstetricians and Gynecologists, and the Centers for Disease Control and Prevention to vaccinate pregnant patients to mitigate severe perinatal morbidity and mortality.  

Read the full study in the journal of Obstetrics and Gynecology.