The size, number and bilaterality of endometriomas do not affect spontaneous conception chance following surgical removal

Objective: Endometrioma surgery is associated with a reduction in ovarian reserve. However, removal of an endometrioma may increase the likelihood of a spontaneous conception. The objective of this study was to assess the pre-operative and operative variables affecting spontaneous conception following endometrioma surgery. Methods: Data from 211 women <= 40 years of age who underwent an endometrioma surgery at a university-based infertility clinic between January 2005 and June 2020 were reviewed retrospectively. The main outcome measure was spontaneous clinical pregnancy. We had 84 women with and 127 women without a successful spontaneous conception making up the case and control groups. Results: The median ages of the cases and controls were 27 and 32 years, respectively (p<0.001). The rate of recurrence was significantly lower in the spontaneous conception group when compared to controls (29.8% vs. 52.8%, respectively; p=0.001). Our results showed no differences in the number, size, or side of the endometriomas in both groups. Multivariate logistic regression analysis showed significant independent effects of age (B: -.166, OR {odds ratio}: 0.847, 95% CI {confidence interval}: 0.791-0.907, p<0.001), recurrence (B: -1.030, OR: 0.357, 95% CI: 0.188-0.678, p=0.002), and laparoscopic surgery rather than laparotomy (B: 1.585, OR: 4.879, 95% CI: 1.029-23.133, p=0.046) for spontaneous conception. Conclusions: The size, number and bilaterality of the endometrioma did not affect the spontaneous conception likelihood following surgical removal. However, increasing age and recurrence are negatively associated with the likelihood of spontaneous conception. Laparoscopic surgery may increase the chance of spontaneous conception when compared to laparotomy.