A new study from the researchers of UT Southwestern Medical Center has found that COVID-19 hospitalizations increased among unvaccinated pregnant women, especially during the surge of the Delta strain, according to Science Daily.

The study, published in the American Journal of Obstetrics and Gynecology, looked at more than 1,500 pregnant women diagnosed with COVID-19 in Dallas County’s public hospital, from May 2020 through September 4.

The researchers found that the number of pregnant COVID-19 patients requiring hospitalization increased from 10 to 15% in late August and early September.

Lead author Dr. Emily Adhikari said, “This is a concerning trend, and we’re primarily seeing these cases in unvaccinated women.”

She explained that the findings suggest that the number of cases and the severity of illness in pregnant women increased with a surge in the Delta variant.

The team found that 82 patients experienced severe or critical illness, including 10 requiring ventilators, and two deaths.

The rate of severe or critical illness was around 5% until after the new year and was then largely nonexistent in February and most of March, according to Science Daily.

However, the number of COVID-19 hospitalizations in unvaccinated pregnant women increased during the surge of the Delta variant in August and early September.

All those 82 patients hospitalized since May 2020 were unvaccinated, except one.

Dr. Adhikari acknowledged that some women hesitate to take the vaccine as they think it may not be safe during pregnancy, but said studies have debunked those concerns.

She said pregnant women are at greater risk for COVID-19 complications so the current findings further emphasize the need for pregnant as well as lactating women to get vaccinated for COVID-19.

Dr. Adhikari said, “If they are exposed and infected, they run a higher risk of severe illness from this most recent Delta variant. Pregnant women should get immunized as soon as possible.”

On Wednesday, the U.S. Centers for Disease Control and Prevention issued urgent guidance recommending pregnant women to get vaccinated against COVID-19. This is CDC’s strongest guidance so far, as the nation reported more than a quarter-million cases in pregnant women, with nearly 22,000 of them getting hospitalized. CDC Director Dr. Rochelle Walensky said, “I strongly encourage those who are pregnant or considering pregnancy to talk with their health care provider about the protective benefits of the Covid-19 vaccine to keep their babies and themselves safe.”