RELATED: CDC urges all pregnant women to get vaccinated against COVID-19
"Early on, it was very understandable to wait for more data," said Dr. Stephanie Gaw, a high risk UCSF OBGYN.
But now, eight months into the vaccine rollout, with safety data from thousands of pregnant women, she says this to expecting moms: "I would recommend going and getting the vaccine as soon as possible. I think it's the best thing that you can do for you and your baby."
But according to the CDC, only 23% of pregnant women have gotten a COVID shot as of July 31, even though pregnant women are more vulnerable to severe COVID infections.
"We've taken care of patients in the ICU, that have been on ventilators for a long period of time, have had to deliver early. And the long term consequences of having such a severe infection during pregnancy for their baby is, you know, is still unknown," said Dr. Gaw.
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One consequence is known. In the largest study of it's kind, a team of UCSF researchers showed that pregnant women infected with COVID are 40% more likely to have a premature baby. And for very premature births, below 32 weeks, the risk increased to 60%.
"When we were submitting this paper, we thought that it might be more historical documenting the pandemic and now with the surge of Delta and the increase in cases that we're seeing among pregnant women, we think these findings are really critical to get out to people," said UCSF epidemiologist, Deborah Karasek, a lead author on the paper.
The study looked at 240,000 expecting California women, who gave birth between July 2020 and January 2021, which means they were not able to be vaccinated at the time.
RELATED: Study finds pregnant women with COVID-19 have higher risk of complications, death
Karasek says it showed people of color face a disproportionate risk. "LatinX birthing people make up about 45% of the population of births, they made up 72% of the COVID infections. And so we really also need to approach preventative measures with an equity lens."
Discovery Bay mom, Hannah Francis, is eight months pregnant with her second child and fully vaccinated. "I got it back in March, April, I had no side effects, I was encouraged by my OB at Kaiser to get it."
Francis says she sees a lot of misinformation on social media about the vaccine in pregnancy, but she's relieved that she was able to protect herself and her unborn baby with a COVID vaccine. "I trust the scientists, I trust the doctors, and I feel very confident that I will have the antibodies to pass onto my newborn."