The effect of selective estrogen receptor modulator administration on the hypothalamic-pituitary-testicular axis in men with idiopathic oligozoospermia

This study evaluates, compares, and contrasts the effects of three selective estrogen receptor modulators (SERMs), namely, tamoxifen, toremifene, and raloxifene, on the hypothalamic-pituitary-testicular axis in 284 consecutive subfertile men with idiopathic oligozoospermia using three therapeutic protocols: [1] tamoxifen, 20 mg, once daily (n = 94); [2] toremifene, 60 mg, once daily (n = 99); and [3] raloxifene, 60 mg, once daily (n = 91). The antiestrogenic effects of SERMs at the hypothalamic level result in a statistically significant increase of gonadotropin levels, which is more marked for tamoxifen and toremifene compared with raloxifene.