Conversion of high-response gonadotropin intrauterine insemination cycles to in vitro fertilization results in excellent ongoing pregnancy rates

Objective: To determine whether conversion of gonadotropin/IUI cycles at high risk of high-order multiple pregnancies to IVF yields a pregnancy rate high enough to warrant the added intervention.

Design: Case-control study.

Setting: Brigham and Women’s Hospital assisted reproductive technology program.

Patient(s): Seventy-seven patients converted from gonadotropin/IUI to IVF, 77 consecutive age and attempt number–matched controls (sequential controls [SCs]), and 77 consecutive age-, attempt-, and E2-matched controls (E2 controls [ECs]).

Interventions(s): Gonadotropin/IUI cycles with exuberant responses were converted to IVF (cases) to avoid cycle cancellation and high-order multiple pregnancies.

Main Outcome Measure(s): Pregnancy rates, delivery rates, E2 levels, follicle and oocyte number, and fertilization and implantation rates.

Result(s): Compared with SCs and ECs, cases had more follicles (16.3 ± 0.6 vs. 13.3 ± 0.9 and 14.4 ± 0.9) and higher E2 at hCG administration (1,951 ± 93 vs. 1,568 ± 96 and 1,939 ± 89 pg/mL). Delivery rates among the three groups (45.5% vs. 32.5% and 39.0%) did not differ significantly. Despite the transfer of fewer embryos in cases than in controls (2.5 ± 0.1 vs. 3.1 ± 0.1 and 2.9 ± 0.1), three triplet pregnancies occurred in cases and three in controls.

Conclusion(s): Conversion of high responder gonadotropin/IUI patients to IVF is an effective alternative to cycle cancellation and offers a delivery rate as high or higher per cycle than that of planned IVF. Sample size limited the statistical power of the study.