In 2016, a study specifically performed on 1337 men with primary couple’s infertility [57], comparing 128 men with MetS (NCEP-ATPIII criteria) and 1209 men without MetS, found lower total testosterone (as well as inhibin B, SHBG and AMH) levels and a higher rate of hypogonadism in the MetS group, but no difference in semen parameters and in the rate of obstructive or non-obstructive azoospermia. This evidence concerns the gene SHBG and hypogonadism.