Comparative analysis of the pregnancy rate via in vitro fertilization vs. previous artificial insemination in patients with unexplained infertility

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, retrospective study from 2016 to 2019, from the Centro Mexicano de Fertilidad Doctor Alberto Kably. The patients with unexplained infertility were divided into two groups, direct in vitro fertilization and a group of in vitro fertilization after intrauterine insemination, and we compared the rate of pregnancy and live births in both cases. RESULTS: 89 couples with unexplained infertility were included, the in vitro 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 noticed 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 the rate of live newborns (32.3 % vs. 14.6%, OR 2.79; 95% CI 1.28-6.07, p=0.008). CONCLUSIONS: In the in vitro fertilization group, as first-line treatment for unexplained infertility, the patients had a higher pregnancy rate.