Administration of atosiban in patients with endometriosis undergoing frozen-thawed embryo transfer: a prospective, randomized study

ObjectiveTo examine the effects of atosiban, given before transfer of frozen-thawed embryo to women with endometriosis (EMs).DesignA randomized, controlled clinical trial.SettingUniversity hospital and IVF center.Patient(s)One hundred twenty women with endometriosis undergoing frozen-thawed embryo transfer were randomly allocated into the atosiban treatment and the control groups. Another 120 women with infertility due to tubal factor were enrolled into a tubal factor group, to compare serum oxytocin (OT) and prostaglandin (PG)F2α levels and uterine contractions with the endometriosis group.Intervention(s)In the endometriosis treatment group, a single bolus (6.75 mg, 0.9 mL per vial) of atosiban was administrated before ET.Main Outcome Measure(s)Implantation rate and pregnancy rate.Result(s)Serum OT level (1.89 ± 0.33 vs. 1.66 ± 0.32 ng/L), PGF2α (2.83 ± 0.34 vs. 2.36 ± 0.35 ng/L) level, and uterine contractions (2.5 ± 1.2 vs. 1.8 ± 1.0 waves per minute) in the endometriosis group were all significantly higher than in the tubal factor group. The clinical pregnancy rate per cycle and implantation rate per transfer were 58.3% and 41.0%, respectively, in the atosiban treatment group, significantly higher than in the control group (38.3% and 23.4%, respectively).Conclusion(s)Women with endometriosis showed higher serum OT level, PGF2α level, and uterine contractions. Atosiban treatment before ET in endometriosis is effective in the priming of the uterus, suitable for embryo implantation. This is the first study to evaluate the effect of atosiban treatment in patients with endometriosis.Clinical Trial Registration NumberChiCTR-IOQ-14005715.