Do ibuprofen and paracetamol affect fertility?

Pain killers, including paracetamol, and non-steroidal anti-inflammatory drugs such as ibuprofen are the most readily-available and commonly-used medicines in the world. This is because they treat non-specific pain (migraines, high temperatures, muscular pain, general discomfort, etc.) and because we, the general public, see them as highly effective and accessible without a prescription.

A few years ago, use of these drugs, which is both generalised and, sometimes, in excess of the recommended dose, encouraged the scientific community to pay particular attention to the side effects of continued and uncontrolled consumption.

But can they affect fertility? If so, are the effects on men and women the same? Are the effects short or long term?

The main concern for most women who are in a fertile age range is whether or not taking medicines of this kind can have a negative impact on their fertility in the short term. In the case of paracetamol, the answer is NO. As far as ibuprofen is concerned, we should take into account that it is usually taken in order to reduce intense menstrual pain which can be a sign of endometriosis and endometriosis itself can be linked to reproduction issues. Little research has been carried out on this subject and its connection to young men. However, it has recently been proven that continued consumption of ibuprofen can cause certain hormonal misalignments that lead to a compensated hypogonadism which is linked to reproduction issues. Nonetheless, more research into this is needed.

Particular care should be taken when taking ibuprofen during pregnancy. Whilst taking ibuprofen is not recommended from week 24 onwards because of the associated risk of malformations, the guides that are available are not so stringent regarding use during the first few weeks of pregnancy. Around 30% of pregnant women take ibuprofen at some point during their pregnancy, either because they are initially unaware that they are pregnant or because they are not familiar with its composition. The first few weeks of pregnancy are crucial to development of the foetus and it would appear that when mothers taken ibuprofen this can affect appropriate development of the foetus’ testes or ovaries. This could have an impact on the next generation’s ability to reproduce. These early conclusions will need to be confirmed when it is possible to study the reproductive health of those generations.

Taking medicine of this kind, therefore, is not currently contraindicated if you are trying to get pregnant, but special care needs to be taken with ibuprofen during pregnancy due to the possible malformations it can cause and the potential impact on the offspring’s future fertility.

Laura Cascales, a biologist at Instituto Bernabeu.