The Icahn School of Medicine at Mount Sinai & RMA of New York Publish Groundbreaking Study on COVID-19 Vaccination and Fertility Outcomes

Follow our #CovidVaxSafe campaign.

Two words that change everything — it’s safe. The Icahn School of Medicine at Mount Sinai and RMA of New York have made a pivotal contribution to COVID-19 vaccination and fertility research with the publication of their manuscript – “In-Vitro Fertilization and Early Pregnancy Outcomes following Coronavirus Disease 19 Vaccination” – found in the latest edition of Obstetrics & Gynecology. The findings add to the growing body of evidence that the COVID-19 vaccination does not affect fertility, and should offer comfort among those trying to conceive or those already pregnant.

This is the largest study to date to review fertility and IVF cycle outcomes in patients who received COVID-19 vaccinations. Patients who participated in the groundbreaking research were treated at RMA of New York between February and September 2021.

This spearheading manuscript is contributing to the greater body of scientific evidence demonstrating the safety and effectiveness of the vaccine.

Read more about the study here.

RMA of New York’s Research in the News

FAQs About the COVID-19 Vaccine & Fertility Study

With the growing number of questions about COVID-19 vaccination and fertility — “Should I get the vaccine if I’m planning to get pregnant?” “Can COVID-19 vaccine cause fertility issues?” — we aim to answer some more common ones by way of our recent published findings. Data-driven and backed by concrete evidence.

The FAQ responses below were provided by Dr. Alan B. Copperman, MD, FACOG: Senior Author, and Division Director and Clinical Professor of Obstetrics, Gynecology and Reproductive Science at the Icahn School of Medicine at Mount Sinai, and Director of RMA of New York; and Dr. Devora A. Aharon, MD: First Author, and Fellow in Reproductive Endocrinology and Infertility at Icahn Mount Sinai, and RMA of New York.

What did this study look at?

This study looked at IVF stimulation and frozen embryo transfer outcomes in patients who were fully vaccinated compared to unvaccinated patients who underwent the same type of cycles during the same time period (February 2021-September 2021).

The IVF stimulation group included 222 vaccinated and 983 unvaccinated patients. This part of the study assessed eggs obtained after ovarian stimulation, number of eggs available for insemination, fertilization rate, and embryo development including genetic composition.

The embryo transfer group included 214 vaccinated and 733 unvaccinated patients who underwent frozen-thawed single embryo transfer of a tested euploid embryo. This arm of the study assessed pregnancy rate (positive HCG), clinical pregnancy rate (pregnancy seen on ultrasound), ongoing pregnancy rate (discharged to OB with a healthy ongoing pregnancy), biochemical pregnancy loss (loss after positive HCG), and clinical pregnancy loss (loss after pregnancy seen on ultrasound).

What did the study show?

The study found that there were no statistically significant differences in any outcomes between the vaccinated and unvaccinated patients.

This study indicates that mRNA vaccination has no harmful effect on IVF stimulation or early pregnancy outcomes. In other words, according to these findings, the COVID-19 vaccination does not affect the outcome of patients undergoing fertility treatment.

What was new about this study/what did it add to our knowledge about the COVID vaccine?

This is the largest study looking at fertility and early pregnancy after COVID-19 vaccination. Studies that have been done previously had smaller numbers of patients or looked at miscarriage rates later in pregnancy, but may have missed very early pregnancy losses. Those studies also showed no differences in outcomes.

This study adds more definitive information about the safety of COVID-19 vaccination for fertility treatment and early pregnancy because of the larger numbers and the focus on IVF pregnancies which are closely tracked. It was able to pick up small differences in egg quality, embryo quality, implantation, early ongoing pregnancy, and early miscarriage – and did not find any differences.

Which vaccines did the study look at and did it compare them to one another?

The study analyzed the mRNA vaccines – Pfizer and Moderna. Other vaccine types were excluded.

The main analysis of the study grouped all vaccinated patients together and compared them to unvaccinated patients, and found no differences in any outcomes.

Subanalyses were also performed looking at the following subgroups:

  • Patients who received the Pfizer vaccine compared to unvaccinated patients
  • Patients who received the Moderna vaccine compared to unvaccinated patients
  • Patients who received the Pfizer vaccine compared to patients who received the Moderna vaccine

No statistically significant differences in any outcomes were seen in any of these subgroups. This indicates that both the Pfizer and Moderna vaccine are safe for fertility and early pregnancy.

Did the study look at the booster shot?

This study did not analyze the booster shot since it came out more recently, and data is still being collected. The booster shot is the same as the original vaccine (half dose for Moderna). We suspect the booster is equally as safe as receiving the original two vaccine doses. We intend to study this
systematically, and once we have more data, we anticipate publish those results as well.

What about partially vaccinated, or vaccinated during the treatment cycle?

Patients who received one dose of the mRNA vaccine, or were less than 2 weeks from the second dose,or received a non-mRNA vaccine, were excluded from the study. This was so that the impact of being fully vaccinated with an mRNA vaccine could be compared to no vaccination without any confusion from partial vaccination or other vaccine types.

All patients in the study were fully vaccinated before starting their cycle. The study did not look at patients who received the vaccine during their cycle. This was in order to assess the impact of being fully vaccinated on cycle outcomes. We have no reason to believe that vaccination during the stimulation cycle, the transfer cycle, or early pregnancy would have any harmful impact.

Did the study assess birth outcomes or impact on the baby?

Because vaccination has only been available for about one year, most patients who were vaccinated before pregnancy have not delivered yet. We are tracking birth outcomes for patients who were vaccinated before their transfer cycle and we plan to publish results once we have enough data.

Many studies have been done in patients who received the vaccine during pregnancy and all have shown that the vaccine is safe. No harmful impacts of the vaccine on the mother or fetus have been seen. Studies have shown that vaccinated pregnant women have a lower risk of severe COVID-19 infection compared to unvaccinated pregnant women, and that the baby can receive protective antibodies from the mother during pregnancy and breastfeeding.

When should I time getting the vaccine or the booster?

The best time to get the vaccine and/or booster is when it is available to you. There is no evidence to prevent or delay vaccination (with one caveat if close to procedure, see below).

a. Can I get the vaccine/booster during pregnancy/should I wait until the second trimester?
All evidence indicates that vaccination is completely safe during pregnancy and poses no harm to the pregnant woman or the developing fetus. This is true during the first trimester as well, and there is no reason to wait.

Fever from any cause during very early pregnancy can theoretically pose some risk to the fetus, though it is very rare to see any harmful effect. It is advised that if you have a fever above 100.4 F as a side effect of vaccination, or from any other cause, to take Tylenol to lower the temperature. To be clear, this is not a harmful effect of the vaccine itself, rather a precaution from fever which can be a side effect of vaccination.

b. Can I get the vaccine/booster during my treatment cycle?

You may get the vaccine or booster shot during your IVF stimulation or embryo transfer cycle, and we have no reason to believe there would be any harmful effect to the cycle.

If you develop a fever or other significant side effects from the vaccine, this may affect your ability to come into the office because we won’t know whether the symptoms are actually from COVID-19 infection. If you just had a procedure, it may be hard to tell if the symptoms are from the vaccine or
from the procedure. Therefore it is advised to avoid getting the vaccine two days before or after your procedure, if possible.

How do we know what we can trust the findings of this study?

This study underwent the complete peer-review process before publication. That means independent experts in the field, analyzed the way that the study was done and the way the data was analyzed tomake sure that the findings are sound.

The journal Obstetrics & Gynecology is the official publication of the American College of Obstetricians and Gynecologists (ACOG) which is the national society for obstetricians and gynecologists and sets the standards of care in the field. It is one of the top OB/GYN journals in the world, and all articles it publishes go through rigorous peer-review to ensure that the findings are valid.

Is it possible that there were baseline differences between the groups, and that there may have actually been a difference in outcomes that was missed?

The study controlled for a number of baseline differences including age, BMI, AMH level, stimulation type, embryo quality, and endometrial thickness. No differences were seen between the groups when controlling for baseline differences. An additional subanalysis was performed where the vaccinated and unvaccinated patients were matched according to baseline characteristics, and no differences were seen in any outcomes.

Where can I read the study?

The study is published online on the Green Journal website. A subscription is not required to access the full article. The article can also be accessed through academic search engines with a university affiliation (Pubmed).

Make an Appointment at RMA of NY

On top of our groundbreaking research, our team is also world-renowned for compassionate, supportive fertility care. Reach out to schedule an initial fertility assessment and consultation with one of our Fertility Specialists.

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Connect with Us on Social Media

With the release of the study, Mount Sinai, RMA of New York, and Obstetrics & Gynecology (the Green Journal) are launching a social media campaign to support COVID-19 vaccination awareness and acceptance. Follow along: #CovidVaxSafe


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