Good News on Pregnant Women and the COVID Vaccine | Healthiest Communities Health News
The gap in data on pregnant people and the COVID-19 vaccine is shrinking slowly but surely, with new findings offering encouraging additions to a growing body of research.
“Things look very good for the association between vaccination and protecting pregnant women from adverse outcomes from themselves and their fetus,” White House adviser and infectious disease expert Dr. Anthony Fauci said at a press briefing this week.
Published by medical journals and indicated by federal data, the new insights come after pregnant people were initially excluded in clinical trials for COVID-19 vaccines, leaving some patients and providers frustrated and grappling with a weighty risk-vs.-reward decision regarding their health and the health of their imminently arriving babies.
Among the new findings: Pregnant people vaccinated against COVID-19 appear able to pass immunity to their newborns through the placenta and breast milk. Dr. Linda Eckert, a professor of obstetrics and gynecology at the University of Washington, says she can use this new evidence in discussions with pregnant patients on whether to get vaccinated.
ACOG has issued recommendations that COVID-19 vaccines not be withheld from pregnant people, but also says patients should be aware that some data is not available. The group notes that none of the available vaccines in the U.S. contain live coronavirus, and its initial recommendations in December came as the early rollout of vaccines targeted priority populations including health care workers, who are overwhelmingly women.
So far, the safety profile of the vaccines in pregnant people has been promising. As of March 29, the CDC says more than 69,000 people who signed up to report their vaccine side effects via its v-safe tool said they were pregnant at the time of vaccination. Nearly 4,000 of those people have been enrolled in a further registry by the CDC, and the agency says data from that registry will be presented at future ACIP meetings and in published reports.
Previously, a March 1 CDC presentation reported that v-safe data as of about mid-February “did not indicate any safety problem” among pregnant women. It also said that “based on presumed COVID-19 vaccine doses administered to pregnant women,” pregnancy-specific issues following a vaccination and reported to the government’s Vaccine Adverse Event Reporting System aligned with the rates at which such problems typically occur.
“No unexpected pregnancy or infant outcomes have been observed related to COVID-19 vaccination during pregnancy,” the presentation said. Its data encompassed doses of the Pfizer and Moderna COVID-19 vaccines, and not of the later-approved Johnson & Johnson vaccine.
Meanwhile, several studies have been published indicating that some level of immunity from a vaccinated mother can pass through the placenta to her baby.
“We are encouraged by what we’ve seen so far,” Dr. Rahul Gupta, chief medical officer for the maternal and infant health nonprofit March of Dimes, says of the studies.
One case study, published by BMC Pediatrics in late March, looked at a health care worker vaccinated with Moderna during her third trimester. Three weeks after her first dose, she gave birth to a healthy newborn girl. Antibodies were detected in the blood of the umbilical cord, indicating the “potential for protection and infection risk reduction” for the infant due to the mother’s vaccination.
Another case study published in March by Obstetrics & Gynecology looked at a health care worker who was vaccinated with the Pfizer vaccine, also during her third trimester. She had been tested for antibodies prior to immunization and had none. Upon delivery after receiving both doses, the study reported the presence of antibodies in the umbilical cord blood and in the mother’s blood.
Neither woman in the studies had tested positive for COVID-19.
Beyond cord blood, there’s also emerging evidence that immunity can be passed through breast milk.
Research published by the American Journal of Obstetrics & Gynecology in late March found evidence that COVID-19 mRNA vaccines – the type made by Pfizer and Moderna – generated a robust immunity response in pregnant and lactating women, and that immunity was transferred via the placenta and breast milk. It provides the first data so far on “maternal antibody generation in response to COVID-19 vaccination” in a large cohort of women.
The study from researchers at Massachusetts General Hospital, Brigham and Women’s Hospital, Harvard University and elsewhere involved 131 women, including 84 pregnant women, 31 lactating women and 16 women who were not pregnant, all of whom received doses of either the Pfizer or Moderna vaccine. The participants were primarily white health care workers; five had previously been infected with the virus that causes COVID-19, including two pregnant and two lactating participants. Serum samples from 37 women who had been infected during pregnancy accounted for another comparison group.
Researchers collected blood and breast milk samples, as well as umbilical cord blood from 10 pregnant women at delivery. They found that pregnant and lactating mothers had comparable vaccine-induced immune responses to those of nonpregnant women, with higher antibody levels than women infected with the coronavirus during pregnancy. Antibodies generated by the vaccine were detected in umbilical cord blood and breast milk; the passage of this immune response between a mother and infant is not an unusual phenomenon when it comes to vaccination.
“Typically, that’s exactly why we give the flu vaccines, as an example,” Gupta explains. “It’s one of the very important public health interventions to ensure that the path of immunity is being developed to give protective antibodies to the newborn, and as well as in utero.”
The study notes that its data does not “elucidate potential risks to the fetus.” Yet researchers found side effects from the vaccine – such as headache, injection site pain, muscle aches and fever/chills – were comparable overall between both the pregnant group and the nonpregnant group.
Still, Gupta adds that pregnant people should be mindful of fever as a side effect.
“In the early trimester, we want to make sure the body isn’t heating too much,” he says. “That’s when the organs are developing … all these important things that happened, that fever can have a deleterious effect on the developing baby.”
Data gaps and questions still remain, study researchers as well as Eckert and Gupta note. For example, larger population studies are needed, as well as studies using the Johnson & Johnson vaccine, which is not an mRNA vaccine and only requires a single dose. Gupta adds that he wants to know more about how the passage of antibodies from a coronavirus-infected mother to an infant compares with the transfer of vaccine-produced antibodies. Research published in December found lower levels of antibody transfer tied to such an infection than expected.
Eckert says she wants to see more studies on how vaccines impact pregnant people in different trimesters, which may help determine if there’s an optimal time to vaccinate pregnant people and facilitate antibody transfer. Additionally, she says, it would be important to know the duration of antibody protection.
These studies come as more states – more than 40, plus Washington, D.C., according to NBC News – have made pregnant people eligible for vaccination.
Both Gupta and Eckert stress that pregnant women who contract COVID-19 face higher risks of severe illness. Gupta says it’s critical that pregnant people, including in Black and other communities of color who have been disproportionately impacted by COVID-19, be prioritized for vaccination. Vermont recently followed Montana in giving people from minority communities priority vaccine status.
“It’s time to ensure that we’re reaching into those areas and those places where we can offer those folks the opportunity to get the vaccine and avoid really terrible but also often a fatal ending to the pregnancy,” Gupta says.