The use of ibuprofen in young men is linked to a risk of male infertility, suggests a study published in the journal Proceedings of the National Academy of Sciences.
Young men taking ibuprofen saw a coordination between luteinizing hormones (LH) – those that produce testosterone – and the level of ibuprofen in their bloodstream.
The study is a continuation of previous research on pregnant women linking mild ibuprofen exposure in fetuses to an increased risk of inherited medical conditions, testosterone blockages, and physiological effects on the testicles of male babies.
A small sample size of 31 male volunteers aged 18 to 35 were split into two groups. The first group was given a daily 600 milligrams dosage of ibuprofen; the second group was given a placebo. Researchers then conducted ex vivo test-tube experiments on human testes provided by organ donors. In both cases, ibuprofen had a direct effect on the testicles.
The decreased ratio of testosterone to LH created a hormonal imbalance called “compensated hypogonadism” in the endocrine system, which regulates and controls hormones. Data shows that ibuprofen selectively represses endocrine cells in the testes, altering the testicular physiology. Hypogonadism is associated with impaired fertility, depression, heart failure, and stroke.
Ibuprofen was of particular interest, the researchers say, because of its increased use in the general population in professional athletes around the world. Over-the-counter pain-relieving analgesics like Motrin and Advil are some of the most commonly used pharmaceutical compounds in the world used to treat aches, pains, fever, and arthritis.
An estimated 25 percent of couples in the developing world are affected by infertility, according to the World Health Organization, and concern over declining male reproductive health has some citing an infertility crisis. Sperm counts in western men have more than halved in the last 40 years and continue to decrease an average of 1.4 percent per year, says a study published in the Human Reproduction Update.
Infertility in men can be caused by a variety of factors including trauma, genetic and hormonal disorders, age, weight, smoking, drug and alcohol use, and environmental toxins. This is the first in-depth study about the effect of pain relievers on the endocrine system, and researchers say while the effects are likely reversible in the test subjects, it will require more research to better understand the long-term effects in bigger populations.