In early 2018, U.S. news agencies reported on a study showing a possible link between the regular use of ibuprofen, an over-the-counter pain medication, and male infertility.
Published in January 2018 in the journal Proceedings of the National Academy of Sciences, the study looked at 31 healthy male volunteers in Denmark and France between the ages of 18 and 35. Fourteen of the subjects took 600 milligrams of ibuprofen daily for six weeks, while the other 17 were given a placebo. Both groups received regular blood and hormone tests throughout the study. At the end of the study, the group receiving ibuprofen showed signs of compensated hypogonadism, a condition in men that may progress to primary hypogonadism. Primary hypogonadism is typically found in older men and may contribute to erectile dysfunction, infertility, and loss of bone and muscle mass.
In addition, the researchers tested the direct effects of ibuprofen on the testicles, using tissue samples from organ donors. After just 24 hours of exposure to levels of ibuprofen similar to those taken by oral ingestion, the testicular tissue produced less testosterone than tissue without such exposure. The study showed that the longer the exposure and the higher the dosage, the more dramatic the effect on testosterone production.
The researchers also found that the effects of lower testosterone production and signs of compensated hypogonadism were completely reversible after short-term usage. The effects of long-term ibuprofen use, however, were not studied and remain unknown.
The Consumer Healthcare Products Association and other critics of the study were quick to point out the study’s small size, as well as the length of ibuprofen use. Other experts in the field of male reproductive medicine also have weighed in.
“It would require more complex experiments involving testicular tissue and sustained exposure to ibuprofen in order to establish a causal relationship between infertility, or sperm production, and ibuprofen,” says Ryan P. Smith, MD, male fertility specialist with Reproductive Medicine and Surgery Center of Virginia, PLC, in Charlottesville. “In addition, the European researchers did not see any significant changes in the expression of genes involved specifically with sperm production.”
The scientists who conducted the research have pointed out that their study did not look at the effects of ibuprofen use on sperm count and other more direct indicators of male infertility—areas that require further investigation.
If you’re taking ibuprofen and are concerned about its possible effects on fertility, talk to your healthcare provider.