new data suggest.
Testicular volume is a fertility marker directly related to sperm count that has halved in the past 40 years worldwide for unknown reasons. At the same time, childhood obesity has risen dramatically and infertility appears to have risen as well, Rossella Cannarella, MD, of the department of endocrinology and andrology, University of Catania (Italy), said at the annual meeting of the Endocrine Society.
According to recent Italian studies, between 14% and 23% of young men aged 18-19 had testicular hypotrophy. “Worryingly, we don’t know the reason for this hypotrophy. And therefore, they are at risk for future infertility,” Dr. Cannarella said during a press briefing.
Her study, which included a total of 264 male children and adolescents, also linked lower testicular volume to hyperinsulinemia and insulin resistance. “The testis is not quiescent in childhood and is sensitive to the hormone insulin. Obesity and metabolic impairment actually can have an effect and negative impact on Sertoli cell proliferation,” Dr. Cannarella said.
Screen testicular volume at all visits
If other studies confirm these results, she said that pediatricians should begin routinely assessing testicular volume at all visits as is now done with height and weight to identify early deflection of the testicular growth curve.
In addition, “include male infertility as a possible consequence of obesity in counseling of male obese children,” she advised.
Asked to comment, Amin Sedaghat Herati, MD, director of male infertility and men’s health at Johns Hopkins Hospital, and assistant professor of urology at Johns Hopkins Medicine, both in Baltimore, said in an interview: “I think what’s really interesting about this study is the association that they’ve made between testicular volume and obesity.”
But, he noted, “it does not implicate necessarily the development of infertility. It’s an extrapolation. So it’s a step towards the link between obesity and infertility, and it’s an important study to establish the association, but changes in testicular volume and even changes in semen panel don’t necessarily indicate fertility or infertility.”
The findings are “consistent with what we know as far as what obesity can potentially do to the activity of the cells in the testes. The authors are postulating that it’s more the support cells, called Sertoli cells, but I would say it’s probably all of the cells that are being affected by obesity and specifically elevated leptin levels,” Dr. Herati said.
He agrees with the recommendation that pediatricians screen all boys for testicular volume. “I agree it’s a good idea so they don’t miss any cases in which the testes don’t develop the way they should or any other conditions,” Dr. Herati said. “I think in general it’s a good practice, especially in the peripubertal stage, to make sure that kids are on the same growth curve and that they’re meeting their Tanner staging. [Pediatricians] should be looking at the size of the testes and tracking, maybe not at every visit, but at least on an annual basis.”
And, he noted, “I think any study that establishes a link that we can point to when we’re educating patients and parents is important.”