OBJECTIVE

To investigate the effect of luteal E(2) supplementation on the pregnancy rate of IVF/intracytoplasmic sperm injection (ICSI) cycles.

DESIGN

A systematic review and meta-analysis of all the randomized controlled trials (RCTs).

SETTING

Tertiary referral center for reproductive medicine and IVF.

PATIENT(S): Women undergoing IVF or ICSI using the GnRH agonist or GnRH antagonist protocol with hMG or FSH for controlled ovarian hyperstimulation.

INTERVENTION(S): Progesterone (P4) alone or combined with estradiol valerate for luteal phase support.

MAIN OUTCOME MEASURE(S): Pregnancy and clinical pregnancy rates per ET.

RESULT(S): An electronic search was conducted targeting all reports published between January 1960 and March 2007. Ten RCTs met the criteria for inclusion in the meta-analysis. There were no statistically significant differences with regard to the main outcome measures, ongoing pregnancy rate per ET, or implantation rate between the group of women who had combined E(2) and P4 therapy and those who had P4 supplementation alone.

CONCLUSION(S): The addition of E(2) to P4 for luteal phase support in IVF/ICSI cycles has no beneficial effect on pregnancy rates. The data in the literature are, however, limited and heterogeneous, precluding the extraction of clear and definite conclusions. A large multicenter, properly designed RCT is needed to further clarify the role of luteal E(2) supplementation in IVF.