Lower calorie diet and weight loss may improve fertility, testosterone2and erectile dysfunction in obese men including men with metabolic syndrome and sleep apnea by altering hormonal profiles, insulin, inflammatory markers, and leptin.
Few studies describe direct effects on fertility, but multiple clinical trials show that testosterone may be improved with an aromatase inhibitor medication (such as anastrazole) by decreasing estradiol, which improves the T to E2 ratio (serum testosterone divided by estradiol).
Obese men with increased estradiol (greater than 10:1 ratio of testosterone to estradiol) are candidates for aromatase inhibitors (anastrazole) which prevents conversion of testosterone to estradiol. In this way, testosterone is increased. By improving testosterone, additional positive changes are noted including increasing lean body mass, decreasing fat mass and waist size, blood sugar, and cholesterol, and potential for improved fertility.
An additional option is surgical management (gastroplasty) to achieve weight loss which is also shown to be beneficial in altering hormonal profiles of some studies of obese men. Other studies show that natural weight loss which is less rapid may be more beneficial to fertility outcomes.
Finally for obese men with fertility issues, IVF/ICSI may be of assistance in cases. Although IVF/ICSI is associated with lower pregnancy rates with obese females, this has not been definitively identified in men10.
Additional large population-based studies are needed to confirm effects of obesity on male fertility and reproductive outcomes.
Source: Fertility Authority