(JACKSON, Miss.) — Mississippi health officials are urging expectant mothers to get vaccinated after a “significant” number of COVID-19 fatalities in pregnant women during the state’s delta surge.

The state health department is investigating eight reports of pregnant women who died from COVID-19 in the past four weeks, all of whom were unvaccinated, Mississippi State Health Officer Dr. Thomas Dobbs said at the top of a COVID-19 briefing Wednesday.

“We do know that COVID is especially problematic and dangerous for pregnant women,” Dobbs said. “We also know it can be deadly for the baby in the womb.”

Compared to the rate pre-pandemic, the health department has seen a “doubling of the rate of fetal demise, or the death of the baby in the womb after 20 weeks,” Dobbs said. “It’s been a real tragedy.”

The warning comes as a majority of pregnant women nationwide have yet to be vaccinated. About three out of four pregnant women in the U.S. have not yet received a COVID-91 vaccine, according to the latest data from the Centers for Disease Control and Prevention.

Pregnant women are at higher risk for severe illness if they contract COVID-19, including “intensive care unit admission, invasive ventilation, extracorporeal membrane oxygenation, and death,” compared to nonpregnant women, according to the CDC.

As of Monday, at least 147 pregnant women had died from COVID-19 nationwide during the pandemic, according to CDC data.

The American College of Obstetricians and Gynecologists, the professional association for OB-GYNs, recommends that all eligible people, including pregnant and breastfeeding women, get the COVID-19 vaccine.

Last month, the CDC also strengthened its recommendation for vaccination in pregnant women, with Director Dr. Rochelle Walensky saying, “it has never been more urgent to increase vaccinations as we face the highly transmissible Delta variant and see severe outcomes from COVID-19 among unvaccinated pregnant people.”

After reporting four COVID-19 fatalities in pregnant women earlier in the pandemic, Mississippi did not have any others again for almost a year, until this past July, state data shows.

“Delta is different, and delta is deadly, and we need to do everything we can to prevent transmission,” Dobbs said.

The health department was still gathering details on the most recent maternal fatalities and the status of the infants, with more information to come next week. It was confirmed that several of the infants were born prematurely, “but are alive,” Dobbs said Wednesday. The health department reported a pediatric death due to COVID-19 on Wednesday, but that was not related to any of the maternal deaths, he said.

Health officials pleaded with pregnant women who had not yet been vaccinated to get the shot, along with the general public. Only 47.6% of Mississippi residents ages 12 and up are fully vaccinated, fourth-lowest in the U.S., compared to 62.5% nationwide, according to CDC data.

“It’s getting easier and easier to find Mississippians that have a story about the tragedy from the delta variant,” Jim Craig, senior deputy and director of health protection for the Mississippi’s health department, said during the briefing. “Don’t let that be a pregnant mom and expectant family.”

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