Vaccines help protect us from serious diseases. But if you’re trying to conceive, you may wonder if vaccines could affect your fertility. It’s a common concern, especially with so much information (and misinformation) online. Here’s what experts know about vaccines and fertility, and what to consider as you plan to start a family.
Vaccines and Fertility: What We Know
Vaccines in general are safe when it comes to fertility, and this safety is well established, says Charis Chambers, MD (“The Period Doctor” on Instagram), a board-certified ob-gyn based in Decatur, Georgia. Multiple studies have found no link between routine vaccines and infertility in men or women, she says.
Plus, vaccine safety is closely monitored, and medical organizations continue to confirm that vaccines don’t affect fertility, says Arielle Bayer, MD, a double board-certified reproductive endocrinologist and infertility specialist at CCRM Fertility in New York City.
It’s worth noting, however, that pregnant women should not receive certain vaccines. But “the vaccines that aren’t recommended in pregnancy — like measles, mumps, and rubella (MMR), varicella (chickenpox), and herpes zoster (shingles) — are contraindicated not because of fertility, but due to theoretical risks to the fetus,” explains Dr. Chambers. This means there’s a possibility that the weakened virus in these vaccines could harm a developing baby. Still, if you’re planning a pregnancy, discuss with your provider to determine when you should be vaccinated.
Let’s look at some of the vaccines that have raised the most questions about fertility.
COVID-19 Vaccine and Fertility
The COVID-19 vaccine has probably gotten more attention than any other vaccine when it comes to fertility concerns. So, what do we know so far?
“There is absolutely no conclusive evidence that the COVID vaccine affects fertility in men or women,” says Alexander Kotlyar, MD, a board-certified reproductive endocrinologist and infertility specialist at Genesis Fertility in the New York City area. A large analysis of 29 studies from different countries found no link between the COVID-19 vaccine and fertility problems.
Research has also confirmed that the COVID-19 vaccines don’t harm ovarian reserve (the number and quality of eggs in the ovaries) or impact sperm health. And major medical groups, including the Centers for Disease Control and Prevention (CDC), the American College of Obstetricians and Gynecologists (ACOG), and the American Society for Reproductive Medicine (ASRM), recommend the COVID-19 vaccine for anyone trying to conceive or already pregnant, says Dr. Bayer. The reason: The benefits of preventing severe COVID-19 disease far outweigh any risks, she says.
MMR Vaccine and Fertility
The MMR vaccine, which protects against measles, mumps, and rubella, has also raised questions about its effect on fertility. But “as with the COVID vaccine, there is no evidence that the MMR vaccine leads to any fertility issues in men or women,” says Dr. Kotlyar.
In fact, if a man isn’t vaccinated and gets infected with mumps, testicular inflammation from the virus could lead to poor sperm development, Kotlyar says.
One important consideration with the MMR vaccine is timing. Because it’s a live, attenuated vaccine — meaning it contains a weakened form of the live virus — experts recommend waiting at least one month after receiving the vaccine before trying to conceive. Although it’s unlikely to happen, there’s a chance the weakened virus could cause disease. “By waiting one month, you allow the immune system to create antibodies (proteins that help your body fight infections) and eliminate all the weakened virus,” says Kotlyar.
HPV Vaccine and Fertility
Because most people get the human papillomavirus (HPV) vaccine as preteens and teens, it’s common to wonder about its effects on future fertility.
Studies have found no association between HPV vaccination and infertility or premature ovarian insufficiency (when the ovaries stop working as they should before age 40). The HPV vaccine may actually protect reproductive health, says Bayer. Here’s how: vaccination helps prevent HPV infections that can lead to cervical precancers and cancers, which may require cancer treatments such as surgery, chemotherapy, or radiation, which impact fertility long-term, she explains.
There are a few reports of early loss of eggs in women after receiving the HPV vaccine, says Kotlyar. But large research studies of many thousands of women showed no increased risk of infertility or early loss of eggs in women after the HPV vaccine, he says. The more patients a study has, the more reliable its results tend to be.
Flu Vaccine and Fertility
Every year, the influenza (flu) vaccine shows up on the list of recommended immunizations. While this vaccine may not be top of mind when it comes to fertility concerns, it’s still an important one to understand.
“Overall, the flu vaccine has not been shown to have an association with fertility in men or women,” says Kotlyar. In one study of more than 8,000 women, researchers found no difference in how likely people were to get pregnant, whether they received the flu shot or not.
Bayer notes that the flu vaccine is not only safe for people trying to conceive, but it’s also highly recommended during pregnancy. Pregnant people who catch the flu are at higher risk of becoming seriously ill, being hospitalized, and experiencing complications, so getting this vaccine helps protect both the parent and the baby, she says.
But if you’re pregnant, stick with the injectable flu shot rather than the nasal spray version. The nasal spray contains a live, weakened form of the virus, which isn’t recommended during pregnancy.
Chickenpox Vaccine and Fertility
If you didn’t receive the varicella (chickenpox) vaccine as a child, or you’re not sure if you’re still protected, your healthcare provider might recommend getting vaccinated before trying to conceive.
And if you’re wondering, there’s no evidence that the varicella vaccine affects fertility in men or women, says Kotlyar. “In fact, it is extremely important that adults be immunized to varicella since infection in adults is often much more serious and deadly than in children,” he explains. He adds that the varicella virus itself can lead to serious damage to a fetus.
But because it contains a weakened virus, the varicella vaccine should not be given during pregnancy. If you’re planning to conceive, you should check your immunity and receive the vaccine ahead of time if needed, waiting at least one month before attempting pregnancy, says Bayer.
How Vaccines Affect Pregnancy
Once pregnancy is on your mind or if you’re already pregnant, you might find yourself questioning decisions that could affect your baby. And vaccines are no exception.
Vaccines play an important role in protecting both you and your future child, says Bayer. For example, the flu, Tdap (which guards against tetanus, diphtheria, and pertussis), and COVID-19 vaccines help reduce the risk of severe illness while passing helpful antibodies to the baby, she says. These antibodies help give newborns an early layer of protection in their first few months of life, before they’re old enough to receive their own vaccines.
On the other hand, unvaccinated pregnant people are more likely to develop severe illness, face complications, or even die from preventable diseases if they become infected. Babies born to unvaccinated parents may also be more vulnerable to life-threatening infections, preterm birth, or low birth weight, says Chambers. To reduce these risks, experts recommend making sure you’re up to date with your vaccines before getting pregnant and following your provider’s guidance on which vaccines to get while you’re pregnant.
Can I Skip or Delay Some Vaccines?
Some vaccines should be timed carefully if you’re trying to conceive. But most recommended vaccines should not be delayed.
The following vaccines are recommended before trying to conceive:
MMR Vaccine Wait one month after your last dose before trying to conceive.
Varicella Vaccine Wait one month after your last dose before trying to conceive.
Hepatitis A and B Vaccines These are safe to receive before pregnancy if you’re at high risk (such as healthcare workers, travelers to certain countries, or people with specific health conditions).
During pregnancy:
COVID-19 Vaccine This is recommended for pregnant and breastfeeding people, any time during pregnancy, and ideally at least two months after your last dose.
Influenza Vaccine This is recommended during any trimester if you’re pregnant during flu season (typically October to May).
Tdap Vaccine This is recommended between 27 and 36 weeks of every pregnancy.
Respiratory Syncytial Virus (RSV) Vaccine A single dose of the RSV vaccine is recommended between 32 and 36 weeks of pregnancy (typically September through January, depending on where you live).
If you missed certain vaccines before or during pregnancy, your healthcare provider may recommend getting them soon after giving birth. This helps protect you from infections and, if you’re breastfeeding, you can pass some antibodies to your baby through breast milk.
Depending on factors like where you’re traveling, what you do for work, or any health conditions you have, your healthcare provider may recommend other vaccines during pregnancy, Chambers says.
There are cases where certain vaccines might not be appropriate. These include if you’ve had a severe allergic reaction to a vaccine ingredient or you’re receiving certain immune therapies. In these situations, your primary care provider, fertility specialist, or obstetrician can guide you based on your health history.
Vaccine Side Effects
Like any medical treatment, vaccines can cause side effects, though most people experience little to none.
Common side effects include swelling and tenderness where you received the shot, fatigue, muscle pain, and a low-grade fever. They’re generally mild, tend to go away on their own, and don’t affect fertility, says Chambers.
Some people have noticed changes in their menstrual cycle after receiving the COVID-19 vaccine. These side effects are also temporary, return to normal within one cycle, and have no impact on fertility, Chambers says.
With so much information online, it can be hard to know what’s accurate. Many concerns about vaccines causing infertility that you might read or hear about aren’t backed by science, says Chambers. If you’re planning a pregnancy, review your vaccine history with your healthcare provider first. And if you ever have concerns after getting a vaccine, discuss them with your healthcare provider.
For accurate and reliable information, Kotlyar recommends checking resources from organizations like ACOG and ASRM. “These organizations publish information that is based on an analysis of the available studies by experts in the field of reproductive medicine,” he says.
The Takeaway
Vaccines — including COVID-19, MMR, HPV, influenza, and varicella — have not been shown to affect fertility in men or women.
Skipping recommended vaccines can increase the risk of severe illness, complications, and even death for pregnant people. It can also make babies more vulnerable to infections, preterm birth, and low birth weight.
Live vaccines like MMR and varicella should be given at least one month before trying to conceive, while the flu, Tdap, COVID-19, and RSV vaccines are safe during pregnancy.
Most vaccine side effects, such as soreness at the injection site, muscle pain, and fatigue, are generally mild and temporary, and they don’t affect fertility. If you have any concerns about vaccines, discuss them with your healthcare provider.
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Zaçe D et al. The Impact of COVID-19 Vaccines on Fertility-A Systematic Review and Meta-Analysis. Vaccine. September 12, 2022.
Pourmasumi S et al. The Effect of Long COVID-19 Infection and Vaccination on Male Fertility; A Narrative Review. Vaccines. November 22, 2022.
Pourmasumi S et al. Effects of COVID-19 Infection and Vaccination on the Female Reproductive System: A Narrative Review. Balkan Medical Journal. May 8, 2023.
Alvergne A et al. Associations Among Menstrual Cycle Length, Coronavirus Disease 2019 (COVID-19), and Vaccination. Obstetrics and Gynecology. January 2024.
Kara Smythe, MD, has been working in sexual and reproductive health for over 10 years. Dr. Smythe is a board-certified fellow of the American College of Obstetricians and Gynecologists, and her interests include improving maternal health, ensuring access to contraception, and promoting sexual health.
She graduated magna cum laude from Florida International University with a bachelor's degree in biology and earned her medical degree from St. George’s University in Grenada. She completed her residency in obstetrics and gynecology at the SUNY Downstate Medical Center in Brooklyn, New York. She worked in Maine for six years, where she had the privilege of caring for an underserved population.
Smythe is also passionate about the ways that public health policies shape individual health outcomes. She has a master’s degree in population health from University College London and recently completed a social science research methods master's degree at Cardiff University. She is currently working on her PhD in medical sociology. Her research examines people's experiences of accessing, using, and discontinuing long-acting reversible contraception.
When she’s not working, Smythe enjoys dancing, photography, and spending time with her family and her cat, Finnegan.
Maggie Aime is a registered nurse with over 25 years of healthcare experience, who brings medical topics to life through informative and inspiring content. Her extensive nursing background spans specialties like oncology, cardiology, and pediatrics. She has also worked in case management, revenue management, medical coding, and as a utilization review nurse consultant. She leverages her unique insights to help individuals navigate the U.S. healthcare system and avoid financial pitfalls.
Maggie applies her extensive clinical expertise to create empowering education for readers at all stages. She is passionate about illuminating issues from disease prevention to health and wellness to medical personal finance. Her work can be found in GoodRx Health, Next Avenue, HealthNews, Insider, Nursing CE Central, Nurse Blake, AllNurses, and BioHackers Lab.
An active member of several professional nursing and journalism associations, Maggie founded The Write RN to fulfill her calling to teach.
When she's not crafting the next great article, you can find Maggie volunteering, reading, playing the piano, or savoring sunrise views at the beach.
