The effect of luteal phase vaginal estradiol supplementation on the success of in vitro fertilization treatment: a prospective randomized study

ObjectiveTo determine whether the use of luteal phase vaginal E2 supplementation improves clinical pregnancy rates in patients undergoing IVF treatment.DesignProspective randomized controlled trial.SettingUniversity-based tertiary fertility center.Patient(s)One hundred sixty-six patients undergoing their first cycle of IVF treatment.Intervention(s)Patients underwent three different protocols for controlled ovarian hyperstimulation for IVF treatment with long GnRH agonist suppression, use of GnRH antagonist, or a microdose GnRH agonist protocol. Luteal phase support was in the form of IM P. Patients randomized into the study group (n = 84) received E2 supplementation in the form of vaginal estrace 2 mg twice a day starting on the day of ET. Patients randomized to the control group (n = 82) received no E2 supplementation.Main Outcome Measure(s)Clinical pregnancy rates.Result(s)There were no significant differences in the implantation (56/210 [26.7%] vs. 64/203 [31.5%]), clinical pregnancy (42/84 [50%] vs. 52/82 [63.4%]), and ongoing pregnancy rates (40/84 [47.6%] vs. 46/82 [56.1%]) between the study and control groups, respectively. In the subgroup of patients who used the long GnRH agonist suppression protocol, there was a lower clinical pregnancy rate in the study group compared with the control group (27/55 [49.1%] vs. 42/59 [71.2%]). There were, however, no differences in clinical pregnancy rates between the two groups in patients who used either the GnRH antagonist or microdose GnRH agonist protocols.Conclusion(s)The addition of vaginal E2 supplementation to routine P supplementation for luteal support does not improve the probability of conception after IVF treatment.