Timing of Estrogen Support During the Luteal Phase of in Vitro Fertilization (IVF)/Intracytoplasmic Sperm Injection (ICSI) Cycle

Timing of Estrogen Support During the Luteal Phase of IVF / Intracytoplasmic Sperm Injection Cycle: a Randomized Controlled Trial

To test the hypothesis that adding estradiol (E2) to progesterone supplementation later in the luteal phase of in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles, rather than earlier in the luteal phase, improves clinical pregnancy rates (PRs).

Several studies reported that elevated E2 may have a detrimental effect on endometrial receptivity and embryo. This conflict was the starting point of our study. The investigators thought that this luteal decrease in E2 level could be prevented by adding estradiol just before the receptivity window is open, instead of adding earlier in the luteal phase which could result in defective embryo implantation.

Inclusion Criteria:

• All patients on long GnRH agonist protocol with controlled ovarian hyperstimulation who were seen in our IVF clinic between February and November 2008, and who have E2 levels on the day of hCG administration >2500 pg/dl

Exclusion Criteria:

• Presence of azoospermia requiring testicular sperm extraction procedure
• endometriosis greater than stage II
• unilateral oophorectomy, polycystic ovarian syndrome (PCOS)
• secondary infertility
• age greater than 40 yrs and a basal follicle stimulating hormone (FSH) level higher than 12 mIU/ml were exclusion criteria