Among the health-care workers first in line for Covid-19 vaccinations will be thousands of pregnant workers left to decide whether to get a shot that hasn’t been tested on those expecting.
States and local governments are preparing to distribute vaccines as early as mid-December, pending an authorization from the Food and Drug Administration. The first rollout will go to frontline health workers and long-term care residents, a group that includes more than 300,000 pregnant or recently postpartum health-care staff. But late-stage clinical trials for Pfizer-BioNTech and Moderna’s vaccines excluded pregnant volunteers.
“The front line category has been prioritized for receiving the vaccine, but little to nothing has been said about whether pregnant women who fit that prioritization category ought to be vaccinated,” Leslie Meltzer Henry, a bioethicist at the University of Maryland and Johns Hopkins University, said. That means there’s very little guidance about how to measure the risk benefit for those pregnant workers.
No red flags have emerged for the vaccine and pregnancy, Geeta K. Swamy, a Duke University physician and researcher who specializes in treating mothers with infectious diseases, said in an interview. “On the other hand, it’s hard to actually look at patients and their families and say, ‘We don’t have any data. We think it’s fine. Let’s go ahead and give you something that is preventative.’”
Pregnancy Linked to Higher Risks
Limited data indicate pregnant women face a greater risk of getting severely ill from Covid-19 compared to non-pregnant women. The vaccine has demonstrated 95% efficacy, showing it works really well in protecting the general population from the disease. At the same time, there’s a lot of general uncertainty about a vaccine platform that has never been used outside of the clinical trial.
“There isn’t a simple answer to questions about whether pregnant people, or those considering pregnancy, should take the COVID-19 vaccine, especially since no vaccine is currently approved,” Christopher Zahn, vice president of practice activities for the American College of Obstetricians and Gynecologists, said in an email. The OB-GYN group is working on guidance to help doctors and patients decide on whether to get vaccinated.
Meanwhile, Flor Munoz-Rivas, a Baylor College of Medicine pediatrician who’s worked on maternal immunization for 25 years, said her inbox has been increasingly flooded with questions as FDA authorization appears imminent. “This has been my every day for the last few weeks.”
Before injecting an experimental vaccine or drug into pregnant women, vaccine manufacturers must conduct animal studies to assure a level of safety. Most companies are nearing the end of those tests, Kathleen M. Neuzil, co-director of the National Institutes of Health’s network of Covid-19 clinical trial sites, said during an Infectious Diseases Society of America press briefing Thursday. Vaccine trials with pregnant volunteers will likely happen in early 2021, Munoz-Rivas said.
Parsing FDA Guidance
FDA decisions on whether to issue an emergency use authorization should come shortly after its vaccine advisory panel meetings Dec. 10 to discuss Pfizer’s vaccine and Dec. 17 for Moderna’s. Both Munoz-Rivas and Swamy said the language in those authorizations will be key. While the agency is unlikely to clear a vaccine for a group that hasn’t undergone testing, the FDA may not expressly prohibit it, allowing pregnant health-care workers and their providers to decide whether it’s right for them.
The Centers for Disease Control and Prevention is waiting on the FDA’s assessment and the conditions in the emergency authorization before issuing guidance on the use of Covid-19 vaccines in pregnant and breastfeeding populations, the CDC’s Sara Oliver said during an Advisory Committee on Immunization Practices meeting Nov. 30. It’s a key question as women comprise 75% of the health-care workforce, and Oliver said 330,000 health-care personnel could be pregnant or recently postpartum during implementation of the initial vaccination.
“We really don’t have a vaccine for everyone until we have a vaccine for pregnant women,” Neuzil, director of the University of Maryland’s vaccine development and global health center, said.
Keeping Options Open
At the same time, safe and effective vaccines for other diseases—including flu, tetanus, and whooping cough—have been administered during pregnancy for decades, even though they aren’t specifically indicated for pregnancy, Munos-Rivas said.
“It’s the same situation right now. As long as we have an active pandemic where people are otherwise exposed and we have a potential option, it’s very difficult to deny a high-risk group the option of being protected when there is a possibility they can be protected with a highly effective vaccine that is likely to be safe,” she said.
“Certainly, the lack of safety and efficacy data will need to be part of the conversation that patients who are pregnant or considering pregnancy will need to have with their obstetrician-gynecologist or other health care professional,” Zahn said in an email.
There will likely be some data on pregnant women from the clinical trials from those who didn’t know they were pregnant when they joined the study, Paul A. Offit, co-inventor of the rotavirus vaccine and director of the Children’s Hospital of Philadelphia’s vaccine education center, said during a JAMA live on Wednesday.
Indeed, a few dozen women have become pregnant during the clinical trials, Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said Thursday during an American Medical Association webinar.