The extent to which BMI, obesity and PCOS phenotypes contribute to the risk of miscarriage in the PCOS populations with RPL as well as putative contributors to underlying pathophysiology, including, inter alia, insulin resistance, serum androgen levels, SHBG, hs-CRP, CTRP6, adiponectin, plasma leptin, homocysteine, AMH and thrombophilia warrant urgent exploration. This evidence concerns the gene SHBG and thrombophilia.