Clomiphene Citrate versus Letrozole for Ovarian Stimulation in Therapeutic Donor Sperm Insemination

<b><i>Aim:</i></b> To compare clomiphene citrate (CC) and letrozole for ovarian stimulation (OS) in therapeutic donor sperm insemination (TDI) cycles. <b><i>Methods:</i></b> Retrospective cohort study between January 2011 and June 2014 at a University-affiliated private IVF clinic in Montreal, Canada. 257 normo-ovulatory women ≤40 years of age with no history of infertility undergoing 590 TDI cycles in the absence of a male partner (single women and same-sex couples) or azoospermia were included. Patients received 100 mg CC daily (145 women, 321 cycles) or letrozole 5 mg daily (112 women, 269 cycles), from days 3 to 7. Only the first 3 cycles were included per patient. Our main outcome measure was cumulative live birth rates (LBR). <b><i>Results:</i></b> Baseline characteristics were comparable between the 2 groups. There were no differences in LBR per cycle (16.5% (53/321) vs. 11.5% (31/269), p = 0.08) and cumulative LBR (36.6% (53/145) vs. 27.7% (31/112), p = 0.13), between CC and letrozole, respectively. Multiple pregnancy rate (11.6% (8/69) vs. 8.7% (4/46), p = 0.6) and miscarriage rate (21.7 vs. 21.7%, p = 1) were also comparable between CC and letrozole, respectively. <b><i>Conclusion:</i></b> In normo-ovulatory women undergoing TDI, OS with CC or letrozole resulted in similar live birth and twin pregnancy rates.