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

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. 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. 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). In the in vitro fertilization group, as first-line treatment for unexplained infertility, the patients had a higher pregnancy rate.