Less miscarriage in pregnancy following Tamoxifen treatment of infertile patients with luteal phase dysfunction as compared to clomiphene treatment.

Objectives: To compare the efficacy and the reproductive outcomes of Tamoxifen (TMX) vs. clomiphene citrate (CC) treatment in infertile women with luteal phase dysfunction.

Methods: Eighty-seven consecutive infertile women with luteal phase dysfunction were randomly assigned to two treatment groups as: group 1 (TMX followed by CC) and group 2 (CC followed by TMX). The medications administered in the initial and the subsequent cross-over phase were given for 4 to 6 cycles except in those patients who achieved pregnancy within the first three cycles of treatment. The rates of pregnancy, spontaneous abortion and live-birth were calculated for comparison. Demographic profile and the frequency of other infertility factors between the two groups were comparable.

Results: The pregnancy rates were similar between TMX and CC treatment (initial treatment phase: TMX, 50.0% vs. CC, 56.4%; subsequent treatment phase: CC, 33.3% vs. TMX, 47.1%), but the abortion rates were significantly lower (p < 0.05) in TMX treatments (initial treatment phase: 8.3% and subsequent treatment phase: 12.5%) than that of CC treatments (initial treatment phase: 22.7% and subsequent treatment phase: 62.5%). When the rates were calculated by pooling the patients according to the medication they received, the miscarriage rate was significantly lower (p < 0.05) if the patients conceived during the TMX treatment (9.4% vs. CC, 33.3%).

Conclusions: Tamoxifen and clomiphene citrate seem to be similarly effective in achieving pregnancy in patients with luteal phase dysfunction. However, Tamoxifen therapy is associated with a lower incidence of spontaneous abortion; thus Tamoxifen may be the better choice for the therapy of infertile women with luteal phase dysfunction.