Effect of bariatric surgery on semen parameters and sex hormone concentrations: a prospective study.

Obesity has become a major health concern, with a prevalence rate approaching epidemic states. An inverse relationship between men's body weight and semen parameters has been observed, suggesting a favourable role for weight loss in improving fertility. This prospective study included 46 patients undergoing sleeve gastrectomy, who were investigated with semen analysis and serum hormone tests before and 12 months after surgery. Patients were divided into three groups according to their initial sperm concentration; median loss of body mass index was used as a cut-off to further classify patients according to extent of weight loss. Patients' preoperative seminal investigations revealed azoospermia in 13 (28.3%), oligospermia in 19 (41.3%) and normal sperm concentration in 14 (30.4%). Overall, only serum testosterone significantly increased after surgery (P < 0.001). Between study groups, the increase in sperm concentration was statistically significant in men with azoospermia and oligospermia (both P < 0.05), whereas serum testosterone was statistically significant in all groups (P < 0.001). Changes in semen and hormone tests were not affected by the extent of weight loss experienced by patients. Weight loss from bariatric surgery had a favourable effect on serum testosterone levels and semen parameters of patients with pre-existing azoospermia and oligospermia.

A systematic review on the genetics of male infertility in the era of next-generation sequencing.

OBJECTIVES: To identify the role of next-generation sequencing (NGS) in male infertility, as advances in NGS technologies have contributed to the identification of novel genes responsible for a wide variety of human conditions and recently has been applied to male infertility, allowing new genetic factors to be discovered. MATERIALS AND METHODS: PubMed was searched for combinations of the following terms: 'exome', 'genome', 'panel', 'sequencing', 'whole-exome sequencing', 'whole-genome sequencing', 'next-generation sequencing', 'azoospermia', 'oligospermia', 'asthenospermia', 'teratospermia', 'spermatogenesis', and 'male infertility', to identify studies in which NGS technologies were used to discover variants causing male infertility. RESULTS: Altogether, 23 studies were found in which the primary mode of variant discovery was an NGS-based technology. These studies were mostly focused on patients with quantitative sperm abnormalities (non-obstructive azoospermia and oligospermia), followed by morphological and motility defects. Combined, these studies uncover variants in 28 genes causing male infertility discovered by NGS methods. CONCLUSIONS: Male infertility is a condition that is genetically heterogeneous, and therefore remarkably amenable to study by NGS. Although some headway has been made, given the high incidence of this condition despite its detrimental effect on reproductive fitness, there is significant potential for further discoveries.