There are no proofs showing that vaccines cause infertility or abortions

The reported cases have never confirmed that the cause of the abortion was the vaccine


A website self defined as Catholic has published an article strongly affirming that messenger RNA (mRNA) vaccines, such as Pfizer’s or Moderna’s, cause abortions and infertility. There is no evidence showing this and the reported cases have never confirmed that the cause of the abortion was the vaccine.

"mRNA vaccine causes infertility, spontaneous abortions […] all over the world"

Doctors in all countries point out that patients coming to their consultations ask whether there exists any risk of sterility and/or abortions after having received it and, in fact, pharmacosurveiilance systems such as the one of U.S. Food and Drug Administration (FDA), so-called VAERS, has received 162 notifications of spontaneous and lost abortions up to date among vaccinated women in the US after receiving the covid-19 vaccine. However, there is no evidence of a decrease in male’s or female’s fertility after receiving the vaccine, nor an increase of spontaneous abortions due to the injections (it should be remembered that the abortion cases reported to VAERS do not necessarily involve causality, nor a proven link, between such an event and the vaccines, but only a temporal coincidence).

“There is not any evidence that vaccines, in particular vaccines against covid-19, can have an impact on fertility, neither in man nor in women”, Adelaida Sarukhan, an immunologist and science writer at the Institute for Global Health (ISGlobal, in Catalan) in Barcelona, strongly asserts to Verificat. In February, The Association of Reproductive and Clinical Scientists and The British Fertility Society published a guide in which it was insisted that there is “no evidence that any of the vaccines can affect the fertility of women or men.

Temporal factors

What can already happen is that, after receiving the vaccine, a series of factors driving to a reduction in the production of spermatozoa can take place, but this is temporal: “Some people have fever one or two days after receiving the vaccine, and it is known that fevers can occasionally cause a temporal decrease of spermatozoa”, points out Sarukan. However, “this effect is temporal”, and similar to the one that a person could experience “if you have fever for other reasons”, for instance, due to a cold or flu”, she concludes.

On the other hand, the guide also raises the possibility to take certain precautions in case of being submitted to a fertility treatment, such as the in vitro fertilisation (IVF) or egg cells freezing. For example, it proposes the spacing of both events (vaccine and fertility treatment) in order to recognise whether the side effects come from one or from another: “It can be sensible separate the vaccination date for some days in case of being involved in treatment procedures (for instance, eggs recollection in a IVF), so that any symptoms, such as fever, can be correctly attributed to the vaccine or to the treatment procedure”, they conclude.

Pregnant women must consult their doctor

So far, vaccines against covid-19 have not yet been recommended in a universal manner for pregnant and breastfeeding women because they were excluded from the clinical trials and there is few data about the efficacy and safety in this group, but there are already some recent studies pointing that, at least mRNA vaccines, are safe in pregnant women.

These reports have made some regulatory agencies, such as the Centers for Disease Control and Prevention, in the US, or the Joint Committee on Vaccination and Immunisation, in the UK, to recommend injections in pregnant women. In other countries, however, the decision must be taken by the woman herself after consulting her doctor to value the benefits and risks that vaccination would have on them depending on their potential risk of virus exposure or if they suffer from any previous pathology able to worsen their condition in case of infection.