Study finds low risk of pregnancy complications from COVID-19

November 19, 2020

DALLAS - Nov. 19, 2020 - Pregnant women who test positive for COVID-19 and their newborn babies have a low risk of developing severe symptoms, according to a new study from UT Southwestern.

The study, published today in JAMA Network Open, shows that 95 percent of women who tested positive for COVID-19 during pregnancy had no adverse outcomes. Additionally, the study found that the virus was transmitted to the fetus in just 3 percent of the cases.

"Our findings are that approximately 5 percent 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)," says Emily Adhikari, M.D., an obstetrician, gynecologist, and first author of the study. "Most women with asymptomatic or mild infection will be relieved to know that their babies are unlikely to be affected by the virus."

The researchers set out to measure how COVID-19 infection impacts pregnancy outcomes, how severely ill a pregnant woman gets, placental pathology, and neonatal infections by studying women at Parkland Health and Hospital System - a high-volume prenatal clinic system and public hospital affiliated with UT Southwestern. The team followed 3,374 mothers, 252 of whom tested positive for the virus during pregnancy, from March through August. The group was predominantly Hispanic (75 percent), followed by Black (18 percent) and white (4 percent). There were no significant differences between the expectant mothers in age, number of previous births, BMI, or diabetes.

The pandemic has hit the Hispanic population in Dallas particularly hard. "While they make up 75 percent of the population of over 12,000 women delivering annually at our institution, women of Hispanic ethnicity made up over 90 percent of COVID-19-positive women. The higher frequency among Hispanic women in our study is consistent with data on racial and ethnic disparities in COVID-19 cases and deaths reported nationwide," says Adhikari, medical director of perinatal infectious diseases at Parkland Memorial Hospital and an assistant professor of obstetrics and gynecology.

Among the 252 women who tested positive, 239, or 95 percent, were asymptomatic or had mild symptoms at first. Six of those women subsequently developed severe or critical COVID-19 pneumonia. Comparing mothers with and without COVID-19 diagnosed any time during pregnancy, the COVID-19 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, and it's hard to predict who that will be. The study found that diabetes may be one factor that increases the risk for severe or critical maternal illness.

Pathologists who examined placentas - the organ that functions as the source of oxygen and nourishment for unborn babies - found that the majority were unaffected by the virus.

COVID-19 mothers 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. Telemedicine has been a vital tool used by many UT Southwestern and Parkland physicians during the pandemic.

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 says. "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."
Other UTSW researchers involved in the study include: Wilmer Moreno, Amanda C. Zofkie, Donald D. McIntire, Rebecca R.J. Collins, and Catherine Y. Spong. Lorre MacDonald of Parkland Hospital also contributed.

About UT Southwestern Medical Center

UT Southwestern, one of the premier academic medical centers in the nation, integrates pioneering biomedical research with exceptional clinical care and education. The institution's faculty has received six Nobel Prizes, and includes 23 members of the National Academy of Sciences, 17 members of the National Academy of Medicine, and 13 Howard Hughes Medical Institute Investigators. The full-time faculty of more than 2,500 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians provide care in about 80 specialties to more than 105,000 hospitalized patients, nearly 370,000 emergency room cases, and oversee approximately 3 million outpatient visits a year.

UT Southwestern Medical Center

Related Preterm Birth Articles from Brightsurf:

Researchers develop app to determine risk of preterm birth
An improved mobile phone app will help identify women who need special treatments at the right time and reduce emotional and financial burden on families and the NHS.

Point-of-care diagnostic for detecting preterm birth on horizon
A new study provides a first step toward the development of an inexpensive point-of-care diagnostic test to assess the presence of known risk factors for preterm birth in resource-poor areas.

WVU biostatistician studies link between microbiome and preterm birth
Pregnant African American women are more likely than white women to give birth prematurely, but they're underrepresented in studies of preterm birth rates.

3D-printed device detects biomarkers of preterm birth
Preterm birth (PTB) -- defined as birth before the 37th week of gestation -- is the leading complication of pregnancy.

Association of quitting smoking during pregnancy, risk of preterm birth
This study of more than 25 million pregnant women reports on rates of smoking cessation at the start of and during pregnancy and also examines the association of quitting cigarette smoking and the risk of preterm birth.

Blood test developed to predict spontaneous preterm birth
Results from a multicenter study show that five circulating microparticle proteins found in first-trimester blood samples may provide important clues about risk of spontaneous preterm birth.

Scientists gain new insight on triggers for preterm birth
A group of scientists led by Ramkumar Menon at The University of Texas Medical Branch at Galveston have gained new insight on a poorly-understood key player in the timing of labor and delivery.

Medically assisted reproduction does not raise risk of preterm birth and low birth weight
Study shows that couples can decide about using medically assisted reproduction free from concerns about increasing the health risks to their baby.

Risk of preterm birth reliably predicted by new test
Scientists at UC San Francisco have developed a test to predict a woman's risk of preterm birth when she is between 15 and 20 weeks pregnant, which may enable doctors to treat them early and thereby prevent severe complications later in the pregnancy.

Preterm birth leaves its mark in the functional networks of the brain
Researchers at the University of Helsinki and the Helsinki University Hospital, Finland, have proven that premature birth has a significant and, at the same time, a very selective effect on the functional networks of a child's brain.

Read More: Preterm Birth News and Preterm Birth Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to