Testosterone adversely affects fertility in some men

Toronto-A recently published study found that a small percentage of men who seek infertility treatment are potentially hurting their ability to have children by taking testosterone supplements.

Most of the men got testosterone through prescriptions, suggesting that many of their physicians don’t realize the potential for harm.

"The good news is that fertility returned for most of the men once their testosterone supplementation stopped. But it may take 6 months or more," said co-author Keith Jarvi, MD, professor of surgery at the University of Toronto and chief of urology at Toronto’s Mount Sinai Hospital, in an interview with Urology Times.

The study, which was presented at the 2013 AUA annual meeting in San Diego and subsequently published online in Fertility and Sterility (2014; 101:64-9), included an examination of the records of 4,400 men who were evaluated for infertility from 2008-’12. All were seen at Mount Sinai Hospital.

A total of 56 patients (1.3%) were taking testosterone supplements at the time of evaluation. Of those, 26, (46.4%) used gels and 25 (44.6%) relied on intramuscular injections. The rest took pellets, oral doses, or unknown formulations and doses.

The findings reflect the experiences of Dr. Jarvi and his colleagues with infertility patients.

"Every now and then, we’d see a young male patient coming through who’d be on testosterone. Sometimes, they were on it for muscle-building purposes or for a decreased sex drive. Quite often they’d be completely unaware that this would have a negative effect on sperm production,” Dr. Jarvi said.

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Many non-urologists prescribing testosterone

Dr. Jarvi said he expected that many of the prescribing doctors would be urologists, but that was not the case.

"It's not just urologists putting these guys on testosterone," he said.

Only three of the men (5.3%) were taking testosterone supplements prescribed by urologists. Prescriptions were more frequently provided by endocrinologists (10, 17.9%) and general practitioners (five, 8.9%). Some testosterone supplements were even prescribed by gynecologists for reasons that aren’t clear, Dr. Jarvi said.

The authors found that the testosterone supplements were indicated for symptoms of hypogonadism (27, 48.2%), symptoms plus low serum testosterone (21, 37.5%), low serum testosterone (four, 7.1%), athletic purposes (three, 5.4%), and low fertility (one, 1.8%).

Eight of the men (14.3%) had Klinefelter’s syndrome. Other co-existing conditions were history of bilateral undescended testicles (seven, 12.5%), Kallmann syndrome (five, 8.9%), Sertoli cell-only syndrome (two, 3.6%), chemotherapy-induced testicular failure (two, 3.6%), prolactinoma (two, 3.6%), anejaculation (one, 1.8%), and opioid-induced testicular failure (one, 1.8%).

The problem is that testosterone supplements lower levels of the hormone in the testicles and lower fertility, Dr. Jarvi said.

"A number of our colleagues aren’t aware of that. They may use testosterone in an older man when fertility concerns aren’t present. But fertility may still be a concern for man who’s 30 or 40, but it’s not in front of the mind of the physician."

Most recover fertility within 6 months

Dr. Jarvi said he and his colleagues have found that about two-thirds of infertile men who are on testosterone recover fertility within 6 months after stopping the supplements.

He cautioned that the rates of men who are infertile and take testosterone may be higher in the U.S. than in Canada, where the study took place.

That sounds right to Ajay K. Nangia, MBBS, professor of urology and director of andrology at the University of Kansas Medical Center, Kansas City. He is co-author of another AUA 2013 study that found that 7% of more than 1,500 men seeking treatment from 2005-’11 were taking testosterone supplements by prescription. The study looked at a pair of clinics in Alabama and Kansas.

More recent data from Kansas show that the rate of patients taking testosterone has grown to 8.9%, Dr. Nangia said. Some men don’t recover fertility after stopping testosterone treatments.

"We are concerned that this represents men who may have had a problem with sperm production and testosterone before they were started on testosterone and were not worked up," Dr. Nangia said.

Why might the percentage of infertility patients on testosterone be lower in Toronto?

"Canada does not have direct-to-patient advertising and places more emphasis on a healthier lifestyle and staying off medication as much as possible,” Dr. Nangia said.

What now? "We should worry about providing more information for young men and clinicians in general on the adverse effects of testosterone therapy," Dr. Jarvi said.UT

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