**10.2 Metabolic syndrome and impact on reproductive health**

Obesity is a cardinal feature of MetSy and has been increasing in [70]. The effect of obesity on reproduction and as a cause of female infertility has been more extensively studied in females [70]. Obesity has been recently associated with an increased incidence of male factor infertility. A study from Norway looked at planned pregnancies and the time to achieving pregnancy, after adjusting for female BMI and smoking habits, the results showed that overweight and obese men had an odds ratio of infertility of 1.19 and 1.36, respectively [71]. Ramlau-hansen et al. [72] conducted a similar study comprising nearly 48,000 couples for six years assessing the effects of both male and female obesity on infertility and found that overweight and obese men coupled with normal- weight females had an odds ratio for reduced fertility of 1.18 and 1.53, respectively. A further observation was that couples where both parents were overweight or obese, the odds ratios for reduced fertility were 1.41 and 2.74, respectively [73]. Obese people have decreased gonadotropin levels, and increased circulating estrogen levels [74]. The increase in estrogen is likely secondary to peripheral aromatization of androgens from cholesterol in the adipose tissue. A hypogonadotropic hypogonadism state is created due to estrogen negative feedback onto the hypothalamus [74].
