Relationship between follistatin expression and clinical outcomes in in vitro fertilization and embryo transfer women with endometriosis

Objective To study the relevance of follistatin (FS) level in follicular fluid (FF) and serum with pregnancy outcomes of endometriosis (EMS) patients undergoing in vitro fertilization and embryo transfer (IVF-ET) and explore the predictive value of FS for IVF pregnancy outcomes in EMS patients. Methods Clinical outcomes and laboratory data from 84 EMS patients (group A) and 80 tubal infertile patients (group B) undergoing IVF-ET in Reproductive Medical Center Department of Obstetrics and Gynecology 900 Hospital PLA from January to June in 2017 were retrospectively analyzed. FS levels in FF on oocytes retrieved day and in serum on human chorionic gonadotropin (hCG) injection day were detected by enzyme linked immunosorbent assay (ELISA), and the correlation between FS and IVF prognosis in EMS patients was analyzed by ELISA. Results There were no significant differences of age, infertility duration, anti-Mullerian hormone (AMH), body mass index (BMI), level of basal endocrine and endocrine on the beginning of gonadotropin (Gn) used between the two groups (P>0.05). Total dosage of Gn used in group A [(2 427.44±894.79) IU] was significantly higher than that of group B [(2 124.69±567.30) IU] (P=0.01). Estradiol level on hCG injection day and oocyte recovery rate in group A [(3 079.46±1 594.12) ng/L, (79.25±13.56)%] were significantly lower than those of group B [(3 701.23± 1 829.01) ng/L, (84.90±12.96)%] (P=0.021, P=0.007). There were no significant differences in Gn used duration, endometrial thickness, luteinizing hormone (LH) and progesterone on hCG injection day, MII oocytes rate, two pronuclei (2PN) fertilization rate, high-quality embryo rate, high-quality blastocyst formation rate between the two groups (P 0.05). The levels of FS in FF and serum in group A were both significantly higher than those in group B (P<0.01). Logistic regression analysis showed that FS level in serum of EMS patients was negatively correlated with IVF pregnancy outcome, while FS level in FF was positively correlated with IVF pregnancy outcome. Conclusion The level of FS in FF and serum were significantly increased in EMS patients. High serum FS level and low FS level in FF were associated with adverse IVF-ET outcomes in EMS patients. The levels of FS in serum and FF have predictive value for IVF pregnancy outcomes in EMS patients. Key words: Follistatin; Endometriosis; Fertilization in vitro; Embryo transfer; Pregnancy outcome