Effects of autoimmune thyroiditis on embryo transfer outcomes in patients with endometriosis
Objective:To investigate the effect of thyroid autoimmunity (TAI) on embryo transfer outcomes of endometriosis patients after assisted reproductive technology.Methods:This is a retrospective cohort study including 483 patients who underwent surgery for endometriosis staging and entered in-vitro fertilization (IVF) stimulation cycles at the Reproductive Medical Center of Peking University Third Hospital from January 2013 to December 2015. Among them, 122 patients were classified as having American Society for Reproductive Medicine (ASRM) stages Ⅰ-Ⅱ and 361 patients as having stages Ⅲ-Ⅳ. The clinical outcomes of embryo transfer were compared between patients with and without TAI in both subgroups.Results:Among the patients with ASRM stages Ⅰ-Ⅱ endometriosis, there were 33 patients with TAI and 89 without TAI; there were no significant differences in the number of retrieved oocytes, high-quality embryo rate, clinical pregnancy rate, or live birth rate between the two groups (P>0.05 for all). Multivariate logistic analysis showed that TSH levels were positively correlated with live birth rate after embryo transfer in patients with ASRM stages Ⅰ-Ⅱ endometriosis (odds ratio [OR]=1.511, 95% confidence interval [CI]: 1.005-2.274, P<0.05). Among patients with ASRM stages Ⅲ-Ⅳ endometriosis, there were 86 patients with TAI and 275 without TAI; there were no significant differences in the number of retrieved oocytes, high-quality embryo rate, clinical pregnancy rate, or live birth rate between the two groups (P>0.05 for all). Multivariate logistic analysis showed that age (OR=0.877, 95%CI: 0.815-0.944, P<0.05) and baseline E2 levels (OR=0.995, 95%CI: 0.992-0.999, P<0.05) were negatively correlated with live birth rate after embryo transfer, while age (OR=1.467, 95%CI: 1.229-1.751, P<0.05) and baseline E2 levels (OR=1.008, 95%CI: 1.000-1.015, P<0.05) were positively correlated with miscarriage rate in patients with ASRM stages Ⅲ~Ⅳ endometriosis.Conclusions:In patients with endometriosis, single-factor and multi-factor analyses suggest that TAI is not a factor affecting clinical pregnancy, miscarriage, and live birth rates in IVF cycles. Age is negatively correlated with clinical pregnancy and live birth rates, and positively correlated with miscarriage rate after embryo transfer.