Received November 19, 2020
Accepted May 29, 2021

Objective: To compare the clinical pregnancy rate among patients undergoing direct in vitro fertilization vs in vitro fertilization after two cycles of intrauterine insemination in couples with unexplained infertility. Methods: Comparative cross-sectional study, retrospective from 2016 to 2019, at the Centro Mexicano de Fertilidad Doctor Alberto Kably. Patients with unexplained infertility were divided into two groups, direct in vitro fertilization and a group of in vitro fertilization after intrauterine insemination, and the rate of pregnancy and live births was compared in both. Results: 89 couples with unexplained infertility were included, the invitro fertilization after intrauterine insemination group (N = 46) and direct in vitro fertilization group (N = 43). The direct in vitro fertilization group resulted in a higher clinical pregnancy rate throughout the study compared to the other group (55.8% vs 34.8%, OR 2.37; 95% CI 1.008 - 5.57, p = 0.046). However, there was no difference in the rate of live newborns (p = 0.12). When analyzing the data by cycle, we were able to observe a statistical difference in both, the clinical pregnancy rate in the direct in vitro fertilization group (38.7% vs 16.7%, OR 3.2; 95% CI 1.50-6.62), as well as in the rate of live newborns (32.3 % vs 14.6%, OR 2.79; 95% CI 1.28-6.07, p = 0.008). Conclusion: In the in vitro fertilization group, as first-line treatment for unexplained infertility, patients demonstrated a higher pregnancy rate.