A WARNING: Don’t take NSAIDs during pregnancy!

Or if you want to get pregnant!

How often do you reach for a pill when you get muscle aches or a nagging headache? Are they NSAIDs such as ibuprofen that you feel pretty safe to take? NSAIDs are pain relievers that are sold over-the-counter and used by multiple millions. But do you know that NSAIDs have been clearly documented to block progesterone signaling? Healthy progesterone signaling is necessary for healthy ovulation. It’s now been shown that healthy pre-menopausal women who take NSAIDs for only 10 days, at the dosage recommended on the label, are at increased risk of infertility. Progesterone is critical for ovulation. NSAIDs block progesterone and suboptimal progesterone signaling then blocks ovulation.

Progesterone also supports pregnancy. In fact, this is how the hormone progesterone got its name—”pro” to sustain and “gestation” meaning pregnancy. Since NSAIDs block progesterone signaling and during pregnancy progesterone is needed to sustain pregnancy, NSAIDs taken during pregnancy have been linked to doubling the increased risk of spontaneous abortion (miscarriage).

If a young woman has blocked progesterone signaling from taking NSAIDs regularly, this inhibition of ovulation is “reversible” as soon as she stops taking these drugs. But there’s now more NSAID issues afoot. When a pregnant woman takes NSAIDs, like ibuprofen, the medication, can cause other nasty issues. NSAIDs can damage the developing testes in the male fetus. This may cause fertility and other issues in her male child as he grows up. These are probably not reversible!

A study conducted by Inserm (Inserm (Institut national de la santé et de la recherche médicale) and researchers at Irset (Institute of Research in Environmental and Occupational Health) shows that ibuprofen “often” causes disruptions in the hormonal system in the human fetal testes.

NSAIDs suppress the production of testicular hormones, including testosterone. Thus, NSAIDs don’t just block progesterone. In the developing male baby, they block the major male hormone and other related hormones. These hormones control the primary and secondary sex characteristics as well as the descent of the testes. Ibuprofen has also been shown to adversely affect parent cells that help produce sperm when the male child becomes an adult. NSAIDS during pregnancy can create downstream negative issues with the development of the male urogenital tract and adult fertility.

This means that taking this over-the-counter pain medication during pregnancy can contribute infertility in your male child when he grows up. How many adult men may trek from doctor to doctor for fertility and hormonal issues, perhaps not finding answers, when the issue began in the womb. This is called “fetal origin of adult disease.”

How many women tramp from fertility treatment to fertility treatment, when it’s the NSAIDs they are grabbing from their bathroom drawers that are the root cause of their infertility?

These hormone disrupting effects of NSAIDs are seen at standard dosages recommended on the label. The male fetus effects were found to occur only when ibuprofen is taken during the first trimester. The first trimester of pregnancy is a well–defined “window of sensitivity” of fetal development. It’s at this time that ibuprofen presents an increased risk for the future genital and reproductive system of the male being exposed to it in the womb.

But the miscarriage risks from taking NSAIDs was found to occur when these medications are taken in the third trimester. So there’s no time throughout an entire pregnancy that taking NSAIDs is completely safe.

How many pregnant ladies take this med? A lot.

Ibuprofen, easily obtained at your local drug store or online, is one of the most commonly used medications by pregnant soon-to-be moms. One woman in ten reports having taken ibuprofen during pregnancy. Yet, more detailed surveys and studies indicate that in reality up to 3 in 10 self–medicate with it. That’s almost 30% of pregnant ladies.

Moral: If you can help it, don’t take meds, even over-the-counter meds, when trying to get pregnant or during pregnancy. Ask your doctor, but also be armed with this information yourself. Not all doctors know about the endocrine disrupting potential actions of NSAIDs. But now you do.

Knowledge is power!


European League Against Rheumatism (EULAR) Congress 2015: Abstract OP0131, Presented June 11, 2015

CMAJ September 6, 2011 First published September 6, 2011, doi: 10.1503/cmaj.110454 Use of nonaspirin nonsteroidal anti-inflammatory drugs during pregnancy and the risk of spontaneous abortion.


Hum Reprod. 2017 Jan;32(1):223-231. Epub 2016 Nov 16. Maternal use of mild analgesics during pregnancy associated with reduced anogenital distance in sons: a cohort study of 1027 mother-child pairs.