COVID-19, the Vaccine, and Female Fertility

I’m a reproductive endocrinologist and OB-GYN who’s been helping people build their families for over 15 years, and in the past two years, I’ve been helping patients build their families in the middle of a pandemic. COVID-19 and the vaccine have been polarizing topics in the world of female fertility. This blog post aims to debunk myths, address misconceptions, and decipher studies to help you feel empowered with your decisions regarding the COVID-19 vaccine and fertility for people with ovaries and eggs. Please see my other blog post on fertility in people that make sperm.

Do COVID-19 infections affect menstrual cycles?

You’ve probably seen the news stories and social media posts about menstrual cycle changes following a COVID-19 infection or vaccination. Much of the buzz has been anecdotal, so let’s unpack the data.

The pandemic was and still is stressful for many reasons, including job insecurity, fear of family member infection, and all of the other unknowns that come with experiencing a pandemic as a generation. A menstrual cycle is intimately related to the hormonal system (especially with consideration to all the communication that needs to take place between the pituitary gland, ovaries, and uterine lining), so it makes sense that stress and illness can change the menstrual cycle. 

Many people are reporting menstrual changes in the pandemic, both related to and not related to COVID-19 infection.One interesting study looked at the self-reported menstrual cycles of just over 12,000 women in a fertility app to see cycle changes during the pandemic: 

• 87% of women reported a disruption in their menstrual cycle, including the length of the cycle itself

• 29% of women reported changes in their menstrual cycle symptoms, ranging from intensified painful periods and heavier bleeding) to subdued (less painful and less bleeding)

• 30% of people who reported some sort of menstrual cycle change during the pandemic while also reporting a change in stress levels

• The users in this study did not report the presence of a COVID-19 infection.

When we are ill, our immune and hormonal systems can change, which might also cause changes in menstrual cycles. One study published in the American Journal of Obstetrics and Gynecology in February 2022 observed a COVID-19 infection’s impact on the menstrual cycle: 

• 127 patients had tested positive for COVID-19 and only 16% reported a change in their menstrual cycle after their infection

• Of the patients who had a change in their menstrual cycle, 60% reported an irregular menstrual cycle (such as shortened, lengthened, skipped) and 45% had increased premenstrual symptoms after their infection

• The patients who reported the most change in their menstrual cycle reported the most severe symptoms from their COVID infection. 

While that study is small, it’s answering a question that many people have: If you get a COVID-19 infection, you can expect a change in your menstrual cycle, but the vast majority of people did not see a change in their menstrual cycle. 

Does the COVID-19 vaccine affect menstrual cycles? 

This was a hot topic in the news after the vaccines were introduced. It’s important to realize that documenting changes in the menstrual cycle was left out of the vaccine trials, which triggered a reminder bias toward men in medicine. It’s the norm to leave out data on menstrual cycles in trials that examine a new medical intervention, but it doesn’t mean it’s okay. Menstrual cycles are not always taken into consideration in medical trials, and I want this to change because menstrual cycles can be reflective of overall health. 

When the vaccine first came out and people were reporting a change in their menstrual cycle, it was concerning for people, particularly those trying to conceive. Finally, in 2022, the American Journal of Obstetrics and Gynecology published a study that looked at the menstrual cycles of almost 4,000 women: 

• Of these nearly 4,000 women, 2,500 got the vaccine and 1,500 did not 

• Most of the vaccinated cohort received Pfizer-BioNTech vaccine (55%) and Moderna (35%); the rest received Johnson & Johnson 

• Women who were vaccinated were asked to track their cycles before and after vaccination 

• It was found that the vaccination changed the number of bleeding days (+1 day), but the overall cycle length (time from the beginning of one menstrual cycle to another) did not change

What does this mean? It’s reassuring that if you got vaccinated, you might see a small change in your menstrual cycle that’s temporary but not lasting. While everyone’s experience is unique, I'm very reassured by the study results.

How does a COVID-19 infection affect female fertility?

Female fertility can be difficult to quantify, but we can get data from ovarian reserve testing, which is essentially a measurement of the quality and quantity of eggs. There are three tests out there that help us look at this:

• Antral follicle count, where we count the follicles in ovaries using ultrasound

• AMH (or Anti-Müllerian Hormone) review, which is a hormone that supports cells around eggs

• FSH (follicle stimulating hormone) review, which gives us a window into egg quality 

  • For more information on ovarian reserve testing, see my blog post or my YouTube video on fertility testing basics

Three studies observed the impact of COVID-19 infection on ovarian reserve: 

• The first study, published in 2021 out of China, looked at AMH concentrations in 91 women with COVID-19 to a control group without COVID-19. The results showed no significant difference in these ovarian reserve tests. 

• Another study published in 2021 specifically looked at patients going through IVF treatment. They observed 65 women with positive SARS-CoV-2 IgG undergoing IVF procedures with 195 women in a control group. There was no difference in ovarian reserve testing in these two populations. 

• Lastly, this study looked at 118 women going through IVF. 14 tested positive for a COVID-19 before their cycle. The AMH levels were compared, and there was no difference between those who tested positive and those without a known infection. 

Based on these studies, data suggests that having a COVID-19 infection does not decrease your ovarian reserves.

Does a COVID-19 vaccine affect ovarian reserve testing? 

This study provides reassuring data that there is no effect on ovarian reserve testing from the COVID-19 vaccine. Published in March 2022, the study observed 129 women ages 18 to 45 before and after receiving two Pfizer COVID-19 vaccines (21 days apart). The findings show that the vaccine did not decrease AMH levels or ovarian reserve. 

We, of course, need to keep doing studies like these ones, but the data we have to date is very reassuring. 

Does a COVID-19 infection impact female fertility? 

One retrospective cohort study, published in 2021, observed women undergoing fertility treatments, which might help answer this question. In this study: 

• 260 women were observed during their IVF cycle

• 65 of the women had previously tested positive for a COVID-19 infection

• 195 of the women had not previously tested positive for a COVID-19 infection

• The outcomes in both group’s IVF cycles were similar 

Another more recent study out of Israel, published in 2022, aimed to get data about previously COVID-19 infections impacting the success rates of IVF:  

• Over 200 patients were included 

• 121 of the patients had a prior COVID-19 infection and were compared to 121 women who had not had a prior COVID-19 infection

• The outcomes were similar

These studies are reassuring for my patients who had a previous COVID-19 infection; data suggests that a previous infection with COVID-19 does not impact success rates for IVF.

Does the COVID-19 vaccine impact IVF outcomes? 

Getting vaccinated decreases the risk of severe disease. We know that pregnant women who get COVID-19 are more likely to end up in the hospital, have ICU admissions, and even face death if they are not vaccinated. Through the lens of fertility treatments, two studies observed the COVID-19 vaccine to IVF outcomes, and the results are encouraging:

• One study evaluated the IVF outcomes of patients before and after the COVID-19 vaccine. The couples were observed for two IVF cycles (one before vaccination, one after vaccination) and had similar numbers of eggs and embryos. There were similar results before and after the vaccine. Keep in mind that this study does not have pregnancy outcomes.

• Another exciting study in 2022 observed 400 patients undergoing IVF (200 vaccinated women compared to 200 unvaccinated women) and found no difference in IVF outcomes in terms of eggs retrieved and embryos created.  

The conclusion of these studies: The vaccine does not change IVF outcomes for women undergoing IVF. It’s also recommended to get vaccinated before trying to conceive to decrease the severity if you get COVID-19 when pregnant.

What are the takeaways about a COVID-19 infection, the vaccine, and female fertility?

The virus, vaccine, and female fertility have been a source of misinformation and fear throughout the entire pandemic. Different studies by different researchers have tried to answer these questions. To recap: 

• Individuals with a COVID-19 infection can see changes in their menstrual cycle, but it is uncertain if these changes are due to COVID-19 or stress

• There may be a slight temporary change in the menstrual cycle’s length due to the vaccine, but this change is temporary 

• As far as ovarian reserve testing, there does not seem to be evidence that getting a COVID-19 infection or vaccine changes female fertility

• With fertility treatment, the data is reassuring: A previous infection of COVID-19 does not change the outcome of IVF cycles, and getting vaccinated does not change outcomes with IVF cycles

Here’s what we also know: Pregnant women are more susceptible to severe disease from a COVID-19 infection. We also know that being vaccinated will decrease the risk of severe disease in women who are pregnant. The recommendation from all medical professional societies is to get vaccinated if you're planning to get pregnant (and to get vaccinated if you're not planning to get pregnant) because it will protect you from the risk of severe disease. If you have further questions, please comment on my YouTube video. We’re in this together.