Selective estrogen receptor modulators (SERMs) are a class of drugs that have an agonistic or antagonistic effect on estrogen receptors depending on the receptor location.24 Clomiphene citrate was the first SERM approved in the USA for ovulation induction therapy in infertile women in 1967.25 Since then, the therapy has been used to treat testosterone deficiency as a non-FDA approved off-label drug.26 Clomiphene citrate improves serum testosterone through competitive inhibition of estrogen receptors in the hypothalamus and pituitary. This evidence concerns the gene ESR1 and Infertility.