Effectiveness of combined tamoxifen citrate and testosterone undecanoate treatment in men with idiopathic oligozoospermia

To assess the effect of treatment with a combination of the antiestrogen tamoxifen citrate and the androgen testosterone undecanoate on sperm variables and pregnancy incidence in men with idiopathic oligozoospermia and couple subfertility. Prospective, randomized, placebo-controlled trial. Clinical research in a tertiary care academic hospital. Two hundred twelve men with idiopathic oligozoospermia and 82 normozoospermic men with female factor subfertility. Oligozoospermic patients were randomly assigned to two treatment groups with tamoxifen citrate, 20 mg/d, and testosterone undecanoate, 120 mg/d (n = 106) or placebo treatment (n = 106) for 6 months. Normozoospermic men were followed for the same period. Couple counseling was part of the intervention in all groups. Pregnancy incidence and sperm characteristics after 3 and 6 months on medication and 3 months after the end of the trial. In the active treatment group, total sperm count (median [25th, 75th percentile], 27.1 × 10 6 cells/mL [9.4, 54.0 × 10 6 cells/mL] at baseline and 61.5 × 10 6 cells/mL [28.2, 119.6 × 10 6 cells/mL] at 6 months), progressive motility (mean [±SD] , 29.7% ± 12.0% at baseline and 41.6% ± 13.1% at 6 months), and normal morphology (mean, 41.2% ± 14.0% at baseline and 56.6% ± 11.5% at 6 months) were noted. No marked changes were observed in placebo recipients or normozoospermic men. The incidence of spontaneous pregnancy was 33.9% in the active treatment group and 10.3% in the placebo group (36 vs. 11 pregnancies), with a relative risk of 3.195 (95% CI, 2.615 to 3.765). Treatment with tamoxifen citrate and testosterone undecanoate improved sperm variables and led to a higher incidence of pregnancy in couples with subfertility related to idiopathic oligozoospermia.