Bariatric surgery does not interfere with sperm quality--a preliminary long-term study

Positive impact of weight loss on sexual function and hormones has been demonstrated, and male fertility in this scenario is to be better defined. We evaluated the impact of lifestyle modifications and gastric bypass on sperm quality.

We prospectively studied 20 morbidly obese men during 24 months, randomized for intervention: lifestyle modifications (exercise and diet) for 4 months and subsequently gastric bypass (n = 10); and control: follow-up (n = 10). All patients underwent International Index of Erectile Function (IIEF-5) questionnaire, serum estradiol, prolactin (PRL), luteinizing and follicle-stimulating hormones (LH and FSH), free and total testosterones (FT and TT) and semen analysis at baseline (time 0), surgery 4 months later baseline (time 1) and final evaluation 24 months (time 2).

Intervention group presented significant reduction in body mass index (BMI) at times 1 and 2, compared to control. There were no significant differences among sperm parameters between groups at times 0, 1, and 2 and among times 0, 1, and 2 in each group. Increases in IIEF-5 score (P = .0469), TT (P = .0349), and FSH (P = .0025) and reduction in PRL (P < .0001) were observed in the intervention group from times 0 to 2 and 1 to 2. Comparing groups at time 2, IIEF-5, TT, and FT increased significantly in the intervention group (P = .0224, P = .0043, and P = .0149, respectively).

Surgery-induced massive weight loss does not interfere with sperm quality, while it increased the quality of sexual function, TT, FT and FSH and reduced PRL. Lifestyle modifications impacted merely the BMI. New studies are warranted, mostly considering birth rate as primary end point and including infertile men.