There is no safety or efficacy data on mRNA vaccines in pregnant women as they were not included in the phase III trials. Both ACIP and the American College of Obstetrics and Gynecology (ACOG) recommends pregnant women be offered counseling to make an informed decision regarding the vaccine. These conversations may include discussion on the likelihood of exposure to COVID-19, potential risks of COVID-19 to them and the baby, and lack of data about the vaccine in pregnancy.
Observational data demonstrate that, while the chances for these severe health effects are low, pregnant people with COVID-19 have an increased risk of severe illness, including illness that results in ICU admission, mechanical ventilation, and death compared with non-pregnant women of reproductive age. Pregnant people with COVID-19 might be at increased risk of adverse pregnancy outcomes, such as preterm birth, compared with pregnant women without COVID-19.
Limited data are currently available from animal developmental and reproductive toxicity studies. No safety concerns were demonstrated in rats that received Moderna COVID-19 vaccine before or during pregnancy; studies of the Pfizer-BioNTech vaccine are ongoing.
Conception Between Doses
In addition, the American Society of Reproductive Medicine recommends that patients who conceive in the window between the first and second dose of the vaccine should be offered the second dose of the vaccine at the appropriate interval.
According to the American Society of Reproductive Medicine, while COVID-19 vaccination can cause fever in some patients, this risk should not be a concern when deciding whether to vaccinate a pregnant individual or a patient desiring pregnancy. While fever in pregnancy (particularly the 1st trimester) has been associated with an increased risk of neural tube defects, a recent study demonstrated the association no longer remained significant if the patient is taking >400 mcg of folic acid daily. Another large Danish cohort study did not demonstrate any increased risk of congenital anomalies of those who reported fever in the first trimester. Additionally, the most common symptom of COVID-19 infection itself is fever (83-99% of affected patients). Patients who experience fever following vaccination should take an antipyretic medication, like acetaminophen.
Johnson and Johnson
Available data on Janssen COVID-19 Vaccine administered to pregnant women are insufficient to inform vaccine-associated risks in pregnancy. We are awaiting recommendations from professional societies.
There are no data on the safety of COVID-19 vaccines in lactating women or on the effects of mRNA vaccines on the breastfed infant or on milk production/excretion. mRNA vaccines are not thought to be a risk to the breastfeeding infant. According to ACOG, COVID-19 vaccines should be offered to lactating individuals similar to non-lactating individuals when they meet criteria for receipt of the vaccine based on prioritization groups outlined by the ACIP.
Johnson and Johnson
Data are not available to assess the effects of Janssen COVID-19 Vaccine on the breastfed infant or on milk production/excretion. We are awaiting recommendations from professional societies.
Updated: March 1, 2021