Treatment of idiopathic oligozoospermia with tamoxifen — a randomized controlled study

SummaryThere is no conclusive evidence of the usefulness of tamoxifen in the treatment of idiopathic oligozoospermia (OAT‐syndrome), as it has been used mostly in uncontrolled studies. We herein report on the controlled treatment of OAT‐syndrome with tamoxifen versus placebo following a randomized design. Seventy‐six men with sperm counts of 2–20 times 106 ml‐1, sperm motility of 20–50%, and sperm morphology (abnormal cells) between 50 and 80% were involved in the study. Patients with varicocele, a history of testicular maldescent or genital inflammation were excluded. Thirty‐nine patients received tamoxifen (30 mg daily), 37 patients placebo. There was a statistically significant increase in the mean serum testosterone level after treatment in the tamoxifen‐treated group (from 4.9 ± 1.9 to 7.9 ± 3.6 ng ml‐1) in comparison to the placebo group (5.3 ± 2.0 and 5.6 ± 2.0 ng ml‐1).serum FSH levels increased slightly in the tamoxifen group (from 6.8 ± 4.1 to 7.3 ± 4.8 mU ml‐1), but this was not statistically significant in comparison to the placebo group (from 5.9 ± 3.9 to 5.2 ± 3.5 mU ml‐1). Serum levels of LH did not show any differences between groups. The sperm count increased during treatment from 9.3 ± 11.7 to 11.4 ± 13.7 times 106 ml‐1 in the tamoxifen group and from 9.1 +‐ 7.1 to 9.3 +‐ 8.8 * 10‐1 in the placebo group; this difference did not reach statiscal significance. The percentage of motile and abnormal sperm was not different between the two treatment groups. In 5 out 37 of the tamoxifen‐treated patients and in 3 out 39 patients of the placebo group, a conception in the female partner was recorded within 9 months after treatment. The fact that the difference in sperm output and pregnancy rate between tamoxifen‐and placebo‐treated men is not statistically significant in out study might be due to the small size of the groups, and a more extensive study might overcome this problem.