Increase in infertility risk linked to painkillers in pregnancy

Taking ibuprofen, aspirin and paracetamol could raise chances of having son with condition that may affect semen production


Mums-to-be who take painkillers have a bigger risk of having sons with a condition that can increase the risk of having poor semen quality, reports the Evening Standard.


The condition is cryptorchidim – or undescended testicles. Undescended testicles are a known risk factor for poor semen quality and also thought to raise the risk of testicular germ cell cancer.

It seems that taking ibuprofen and aspirin in the fourth, fifth or sixth month of pregnancy can quadruple the chance of a baby boy being born with cryptorchidim. Taking paracetamol doubles the risk. However, the risk is increased by 16 times if more than one type of painkiller is taken at the same time.

The findings seem to back up what a previous study found. This other study revealed that painkillers upset the production of a steroid hormone, androgen. This leads to insufficient testosterone supplies at the time male organs are developing.

The new results come from studying 384 women in Demark and 1,463 women in Finland. While the results are concerning, and have seen fertility expert Dr Allan Pacey, from the University of Sheffield, call for more research, there are a few issues that could mean the picture isn’t as clear as it should be.

Firstly, the mums in Denmark answered a written questionnaire, had a phone interview, or did both. The questionnaire didn’t specifically ask about taking painkillers while pregnant, and when answering the questionnaire, 31% wrote that they’d taken painkillers. The phone interview did ask about mums-to-be taking painkillers, and so on the phone, 57% said they’d used painkillers. Of these, a noteworthy number of the boy babies showed signs of cryptorchidim.

The mums in Finland just undertook a written questionnaire, which didn’t specifically ask about using painkillers while pregnant. The findings in Finland weren’t as considerable as they were in Denmark. The researchers think this is down to the mums under-reporting their painkiller use, because they probably didn’t think of such mild painkillers as “medication”.

The current Government advice suggests that, while some painkillers are considered “safe”, mums-to-be should check for taking anything.


We’ve rounded up safer remedies for pregnancy illnesses, aches and discomforts, plus an overview of what’s safe in pregnancy and what you should avoid. Also, check out our look at medicines in pregnancy.

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