SHBG and obesity due to melanocortin 4 receptor deficiency: The consequences of obesity in female fertility have been widely studied, but studies in the male population are less frequent.(12) It has been postulated that obese men have an increased risk of erectile dysfunction.(13) It has also been proposed that overweight and obesity in men can lead to a drop in levels of sex hormone-binding globulin (SHBG), increasing the levels of estradiol and altering secretion of gonadotropins.(14,15)