Selection of oligozoospermic men for tamoxifen treatment by an antiestrogen test

In a retrospective study 46 men with idiopathic normogonadotropic oligozoospermia were treated by 20 mg Tamoxifen daily for a period of 6 months. A significant improvement of sperm count, total sperm output, total and progressive motility as well as sperm morphology was observed. In 25 men before initiation of treatment a short-term antiestrogen test with daily 40 mg Tamoxifen for a period of one week was performed with assessment of serum levels of testosterone, LH and FSH before and afterwards. Considering hormonal response in those patients who showed a more than 50% increase of sperm count (responders), FSH levels after Tamoxifen administration were unaffected. In contrast, a significant increase of the FSH level was observed in the group of the non-responders. Serum testosterone and LH levels increased in both groups, but showed no obvious differences. A similar hormonal pattern was found in father's and nonfather's concerning the response of FSH after Tamoxifen administration. It is concluded that the response of FSH towards Tamoxifen may be of use to predict improvement of semen parameters and therefore seems to be suitable to select patients for Tamoxifen therapy.