Improving reproductive outcomes in frozen embryo transfer over fresh embryo transfer in women with endometrioma: A historical cohort study

Background: Endometrioma, a common manifestation of endometriosis, often indicates the severity of the disease. In vitro fertilization and embryo transfer (ET) are key therapeutic strategies for infertility associated with endometriosis. However, the optimal type of ET (frozen or fresh) and its impact on pregnancy success rates remain debated, with limited studies available. Objective: This historical cohort study aimed to compare fertility and neonatal outcomes, focusing on live birth rate (LBR), clinical pregnancy, and implantation rates in women with endometrioma-associated infertility, between fresh and frozen embryo transfer (FET). Materials and Methods: In this historical cohort study, the medical records (files) of 289 women diagnosed with endometrioma-related infertility, who underwent in vitro fertilization/intracytoplasmic sperm injection treatment at Royan Institute, Tehran, Iran between March 2016-2021 were reviewed. Ultimately, 200 files that met the established criteria were selected for review. The extracted data was then compared between groups: FET (n = 121) and fresh ET (n = 79). Results: No significant differences were observed between the groups in terms of demographic characteristics and endometrioma size. The only significant difference in fertility outcomes was the LBR, which was 36.4% for the FET group compared to 22.8% for the fresh ET group (p = 0.04). No significant differences were observed in neonatal outcomes between the groups. Overall, our study suggests that FET may lead to higher LBRs in women diagnosed with endometrioma. Conclusion: Our study suggests that FET may lead to higher LBRs in women diagnosed with endometrioma.