Could the COVID vaccine lead to infertility?

Could the COVID Vaccine Lead to Infertility?

The idea that COVID-19 vaccines cause infertility has circulated widely, but a careful look at the science shows no credible link. Here's what you need to know:

1. How COVID-19 Vaccines Work

   • mRNA Vaccines (Pfizer-BioNTech, Moderna) teach your cells to make a harmless piece of the coronavirus's spike protein. Your immune system then learns to recognize and fight the real virus if you're exposed.
   • Viral-Vector Vaccines (Johnson & Johnson, AstraZeneca) use a harmless virus to deliver instructions to your cells, also prompting an immune response.
   • None of these vaccines contain live coronavirus, so they cannot cause COVID-19 or directly harm reproductive organs.

2. Why the Infertility Myth Started

   • A misplaced concern arose that the spike protein is similar to syncytin-1, a protein involved in placental development. In reality, the two proteins share only a tiny, biologically insignificant sequence.
   • No antibodies generated by vaccination cross-react with syncytin-1 or other fertility-related proteins.
   • This rumor persisted despite no laboratory or real-world data to back it up.

3. Evidence from Reproductive Studies
   a. Female Fertility

   • Bentov et al. (2021) studied women undergoing in-vitro fertilization (IVF). They found that COVID-19 infection did not change hormone levels or egg quality—and vaccination had no negative effect either.
   • Ongoing monitoring of thousands of vaccinated women shows normal rates of conception, miscarriage, and healthy births.
     b. Male Fertility
   • Multiple studies measured sperm count, motility (movement), and shape before and after mRNA vaccination. Results show no significant changes.
   • Temporary, mild fever after vaccination can briefly affect sperm parameters (as happens with other vaccines or infections) but values quickly return to normal.

4. Professional Guidance
   Major health organizations agree there's no reason to fear infertility from COVID-19 vaccines:

   • American College of Obstetricians and Gynecologists (ACOG)
   • American Society for Reproductive Medicine (ASRM)
   • European Society of Human Reproduction and Embryology (ESHRE)
   • World Health Organization (WHO)

5. COVID-19 Infection vs. Vaccination
   Getting COVID-19 itself can carry risks to reproductive health and pregnancy:

   • Severe illness in pregnant people is linked to higher rates of preterm birth, intensive care stays and, rarely, pregnancy loss.
   • High fevers and systemic inflammation from infection can temporarily affect sperm and egg health—yet these effects are short-lived and reversible.
     Vaccination prevents severe disease, reducing these infection-related risks.

6. Real-World Safety Data

   • Over 200 million women worldwide have been vaccinated and tracked through pregnancy registries. No increase in birth defects or long-term fertility issues has been found.
   • More than 17,000 completed pregnancies in vaccine trials and safety monitoring systems show outcomes in line with pre-pandemic norms.

7. Common Questions
   • "Can I get pregnant right after vaccination?"
   Yes. There's no recommended waiting period.
   • "Should I pause fertility treatments to get vaccinated?"
   No. Delaying vaccination leaves you vulnerable to COVID-19, which can complicate pregnancy and fertility procedures.
   • "What if I'm trying to conceive?"
   Vaccination is the best way to protect both you and a future pregnancy from COVID-19 complications.

8. Other Credible Resources

   • Centers for Disease Control and Prevention (CDC): FAQs on pregnancy and COVID-19 vaccines
   • World Health Organization: Vaccine safety and monitoring
   • Peer-reviewed journals reporting on reproductive health and COVID-19

9. What to Do If You Have Symptoms
   If you're experiencing cough, fever, loss of taste or smell, or other concerning signs, use Ubie's free AI-powered symptom checker to assess your COVID-19 symptoms and receive personalized guidance on whether you should get tested or seek medical care.

10. When to Speak to a Doctor
    Always reach out if you experience:

• Severe or persistent abdominal pain
• Heavy vaginal bleeding
• Symptoms of infection after fertility procedures
• Any life-threatening or unusual signs

Your healthcare provider can best address individual risks, guide fertility planning, and manage any urgent concerns.

Bottom Line
There is no scientific evidence that COVID-19 vaccines cause infertility in men or women. On the contrary, vaccination protects reproductive health by preventing the complications of acute infection. If you have specific fertility questions or medical conditions, be sure to speak with your doctor—especially if you experience serious symptoms.