A: There is no scientific evidence to suggest COVID-19 vaccines negatively impact fertility in men or women.
While these vaccines were not tested among pregnant people for initial FDA Emergency Use Authorization in the United States, accumulating data support the safety of COVID-19 vaccines in people who wish to become pregnant and people who are currently pregnant.
Joining us for this post is Nerdy Guest Dr. Marissa Steinberg Weiss, MD from the Center for Reproductive Medicine at the University of Michigan.
First, the biologic function of mRNA vaccines does not impact fertility or placenta formation. The Pfizer and Moderna COVID-19 vaccines do not contain syncyntin-1 or the mRNA sequence to create syncyntin-1 as reported in a widely circulated article that falsely claimed these vaccines could prevent human placenta development. Additionally, mRNA vaccines are not made from live virus. Live virus vaccines are not recommended in pregnancy.
There are no studies linking COVID-19 VACCINATION to infertility in people who produce sperm. A small study did find lower sperm counts with COVID-19 INFECTION. The study looked at 33 people who produce sperm at one timepoint and does not examine male fertility over the course of COVID-19 recovery. Studies are underway looking at short term changes in fertility due to COVID-19 disease, like a temporary drop in sperm count following a fever. At present, there is no plausible link between COVID-19 VACCINATION and infertility.
Research continues on reports of changes to menstrual cycles following COVID-19 vaccination. Menstrual cycles can change for a number of biologic reasons and typically return to their previous patterns without intervention. Theories for changes in menstrual cycles following COVID-19 vaccination include a strong immune response, lowered platelets, and physiologic stress. Like other vaccine side effects, these factors are transient and do not impact the ability to conceive.
The J&J vaccine has not been linked to infertility in any studies. There is less data available examining the J&J vaccine in pregnant people and people trying to conceive as this vaccine has been available for less time in the US. At this time, the Advisory Committee on Immunization Practices states the benefits of the J&J COVID-19 vaccine outweigh the risks and the vaccine remains available to people aged 18-49 years of age with a warning about the risk of rare blood clots.
It’s important to consider the risks of vaccination in the context of the very real and substantial risks from COVID-19 itself. Pregnant people with COVID-19 have 3 times the risk of non-pregnant people of similar age for ICU admission, as well as higher risk for requiring mechanical ventilation and dying. COVID-19 poses risks to both the pregnant person and the unborn fetus. A recent study found that people who were infected with COVID-19 during pregnancy were at increased risk of premature birth, pre-eclampsia, and other neonatal complications. We know that pregnant people who receive the vaccine pass on protective antibodies to their babies via the placenta and breastmilk. Additionally, tens of thousands of pregnant and hoping to become pregnant people have already received COVID-19 vaccinations with no adverse responses.
Multiple national and global organizations recommend COVID-19 vaccination for pregnant individuals and people attempting pregnancy given the known risks and severity of COVID-19 disease during pregnancy. Organizations supporting COVID-19 vaccination for pregnant people and those who wish to become pregnant include the US Center for Disease Control (CDC), the American College of Obstetrics and Gynecology (ACOG), and the Society for Maternal-Fetal Medicine (SMFM), the World Health Organization (WHO), and the American Society for Reproductive Medicine (ASRM).
Concerns surrounding fertility and pregnancy are sensitive and should be taken seriously. If you have questions, reach out to your healthcare team. Many studies are underway to further examine the effects of COVID-19 vaccine and disease on pregnant people and neonates. To date, no studies suggest the COVID-19 vaccinations negatively affect fertility or pregnancy. As new information becomes available, Those Nerdy Girls will continue to provide up-to-date information.
Those Nerdy Girls
*This post was updated on 5/2/2021 at 5:25 PM to include more inclusive language.