Does luteal estradiol supplementation have a role in long agonist cycles?

ObjectiveTo test the hypothesis that the addition of 6 mg estradiol (E2) valerate either orally or vaginally to progesterone (P) for luteal support, can increase the probability of pregnancy in intracytoplasmic sperm injection (ICSI) cycles using the long agonist protocol.DesignProspective open-labeled randomized controlled trial.SettingPrivate and university fertility centers.Participant(s)Women undergoing ICSI cycles, with controlled ovarian hyperstimulation using long agonist protocol.Intervention(s)On embryo transfer day, participants were randomized to receive, only P (group A, n = 90), P along with 6 mg E2 valerate either orally (group B, n = 90), or vaginally (group C, n = 90) for luteal support.Main Outcome Measure(s)Clinical pregnancy was the main outcome. luteal serum E2 and P profiles were the secondary outcomes.Result(s)Highest pregnancy rate was achieved in group C (45.56%), it was significantly higher than A (relative risk 1.52, 95% CI: 1.03 to 2.24). Day 0 (hCG day) E2 levels were similar in the three groups. Group A had lower E2 levels on days 7, 10, and 13 and a higher magnitude of E2 decline on days 7 and 10. Similar levels of luteal E2 were documented in groups B and C. P levels were similar in the three groups.Conclusions(s)Addition of 6 mg E2 valerate to P support may encumber the sharp decline in luteal E2 level. It may enhance the probability of pregnancy if administered vaginally.