The United States’s emergency authorization of Pfizer’s COVID vaccine in the U.S.—shown to be 95% effective in large-scale clinical trials—feels, for many, like a turning point in the pandemic. As an ICU nurse in Queens became the first New Yorker to receive the vaccine on Monday, it has inspired something that has been, thus far, unfamiliar this year: a sense of hope and promise. But it’s also inspired a litany of questions: When will the rest of us receive it? Where will it be available? Will it be free? And beyond the logistics, there are the broader concerns for some about the vaccine’s safety, specifically among people who are pregnant or trying to conceive, and for parents of younger children, all of whom have been, so far at least, excluded from clinical trials. As of December 11th, the FDA will allow pregnant and lactating women to access the vaccine, even if it hasn’t been tested on them, but it remains unavailable for anyone under 16. Because we are so early on in the vaccine timeline, the answers for many questions remain to be seen.
To walk us through what we know and what we don’t know about the vaccine as it relates to maternal health, we asked two experts whose specialties lie in treating and studying women and children—Heidi K. Leftwich, DO, an assistant professor of obstetrics and gynecology in UMASS’s Division of Maternal and Fetal Medicine, and Kelly Fradin, MD, a New York-based pediatrician and author of the recent (and very timely) book, Parenting in a Pandemic.
Historically, pregnant and lactating women have been excluded from clinical and vaccine trials because of safety concerns for the mother and child. But that exclusion can pose its own risks, a point that’s been repeatedly raised by The Society of Maternal Fetal-Medicine and various medical professionals. “It’s common and it’s a cause for concern,” says Fradin. “When the consequences of toxic medications DES and Thalidomide were noted in the 1940s and 1960s, in 1977 the FDA barred pregnant and lactating women from phase 1 and phase 2 studies. This was intended to increase the safety of pregnant women, embryos, and infants. However, functionally this leads to barriers including women of reproductive age in medical research which leads to less knowledge, advancement, and innovation in women’s health.” It’s a problem that many national societies are working tirelessly to rectify in the future. “Many are advocating to ethically include pregnant and lactating women in future clinical trials, but until this is more commonplace, physicians and other healthcare practitioners will need to continue to monitor updates in the data to best inform their patients regarding the COVID-19 vaccines,” adds Leftwich.
In short, yes, simply because pregnancy itself is designated high risk for the development of severe disease, hospitalization, and even death, says Leftwich. “The MMWR [Morbidity and Mortality Weekly Report from the Centers for Disease Control and Prevention] estimated that pregnant women are at three times higher risk for requiring admission to an ICU or requiring a ventilator [because of COVID-19], and that their risk of death is about 70% higher than their non-pregnant peers,” adds Fradin. That risk is compounded for pregnant women of color. The maternal death rate for black mothers is already double the rate of white mothers, and, nationally, Black and Latina women are disproportionately affected by COVID-19 during pregnancy. So grave are the concerns around COVID-19 and maternal mortality that legislation to address the issue was introduced this year by Massachusetts Senator Elizabeth Warren and Representative Lauren Underwood of Illinois.
“Women in healthcare face many layers of concern about coronavirus, becoming sick due to potentially increased exposure, experiencing pregnancy complications due to infection, and infecting their family members or patients,” says Fradin. “Accordingly, these women may feel that the benefits of the vaccine for their health, their family’s health, and their patients health are considerable and sufficient to justify taking a vaccine which is likely safe before having access to further research.” The Society for Maternal Fetal Medicine has been highlighting the heightened risk to pregnant healthcare workers and advocating on their behalf for vaccine access, should they elect to take it.
The UK’s regulatory health agency, the MHRA, advised against pregnant and lactating women using the vaccine, but, as of a few days ago, the U.S. FDA has given the go-ahead. Groups including the American College of Obstetrics and Gynecology and The Society for Maternal Fetal Medicine are supporting the vaccine being offered to pregnant and lactating individuals. Though there isn’t currently data that offers additional reassurance, many experts say that the general CDC guidelines for vaccinating pregnant women should apply: that when the likelihood of disease exposure is high, the benefits outweigh the risks. But the decision will, ultimately, come down to the pregnant individual, and whatever they decide should be supported. Like so many things that come up when you’re pregnant or trying to conceive, be prepared to talk about the merits of vaccination with your doctor or practitioner. “The most important things to discuss with your doctor is the risk of contracting the virus, risk of severe disease due to comorbidities and the most current safety data available,” adds Leftwich.
Despite nursing mothers being excluded from Pfizer’s clinical trials, the Academy of Breastfeeding Medicine released a statement yesterday stating that, for individuals who are vaccinated against COVID-19, they do not recommend the cessation of breastfeeding. According to Fradin, there is no reason to suspect the vaccine would be unsafe for those who are breastfeeding. “There is no component of this vaccine which poses a particular concern, nor is it a live vaccine that will replicate or spread significantly beyond locally at the injection site where it will generate spike protein,” she says. The ABM’s statement underscores that it is unlikely that the vaccine lipid would enter the bloodstream and reach breast tissue, and if it did, it would be even less likely that the intact nanoparticle or mRNA would transfer into milk. Fradin adds that the protection from the vaccine will likely extend to the nursing infant as well. “We know from experiences with other illnesses that vaccinating the caregivers and parents protects the children and infant from exposure to the virus, so this cocooning is an indirect benefit to consider.”
The limited data makes this a particularly difficult question. “Early pregnancy is the time when fetal development occurs and typically poses the largest risk to anomalies from any medical or environmental exposure,” Leftwich explains. “Therefore, though no specific concerns have been noted at this time, the vaccine at the time of conception should likely be avoided if and when possible.” Leftwich recommends that women who wish to get vaccinated obtain the vaccine, then wait two to three months before conception. “This would provide substantial protection throughout their pregnancy with minimizing even the theoretical risk,” she explains. For anyone trying to conceive, the most important thing to do is engage in a discussion with their doctor about the risks and also keep in mind that more data is becoming available every week.
As of now the vaccine remains unavailable to anyone under 16, though clinical trials are beginning in adolescents. The most recent recommendations included children 16 and up, and Pfizer began enrolling children 12 years of age and older in their ongoing trials in September. Fradin suspects that we’ll start to see younger individuals enrolled in studies soon and, if they go well, vaccines will be recommended for those age groups. “While some parents may be disappointed their children can’t be vaccinated sooner, I would remind them children haven’t been prioritized because they are at lower risk for serious complications from coronavirus,” she explains. Despite that, Fradin imagines it will be recommended to prevent rare complications and to reduce community spread. And Fradin is eager to debunk the concern among parents of the MIS-C immune complication of coronavirus in children who are vaccinated. “Adults have also had a similar syndrome under age 40 referred to as MIS-A and, despite observation for more than two months, we haven’t seen this occur in any of the adults who have been vaccinated or the small number of teens,” she says.
It remains unclear what age will be selected as the youngest for administration of the vaccine, but, besides hepatitis B, most vaccines aren’t ever even offered to infants under two months. “Since newborns are at higher risk for bacterial illness, it can be difficult to sort fever requiring a work-up from fever due to the vaccine,” says Fradin. “But if mothers are vaccinated or immune, the antibodies shared through the placenta will provide partial protection to the infant up to 6 months of age in addition to antibodies shared by breastfeeding.” Even with children who are older, the cocooning effect of vaccinated parents and caregivers offers some insulation against the virus. Though, as Fradin points out, older children also tend to be in contact (through school, activities, etc.) with more children who may not be able to be vaccinated yet. Protection increases with the amount of people around them who are vaccinated, adds Fradin. “Cocooning is more dependent on vaccine uptake amongst all the adults in a community.”