Estradiol Level on Day 2 and Day of Trigger: A Potential Predictor of the IVF-ET Success.

OBJECTIVE To evaluate role of serum estradiol levels in predicting likelihood of pregnancy in women undergoing GnRH-a protocol in IVF-ET cycles. DESIGN A 3-year retrospective analysis of estradiol levels on down-regulated day 2, day 6, and day of hCG trigger and subsequent clinical pregnancy rates. SETTING A university hospital tertiary referral centre. POPULATION OR SAMPLE Women undergoing IVF treatment. METHODS Hormonal assessment on the down-regulated day 2, day 6, and day of hCG trigger. MAIN OUTCOME MEASURES Comparison of hormonal profile, antral follicular count on day 2, endometrial thickness on day of trigger, and number of oocytes retrieved between pregnant and the non-pregnant group. The prediction of IVF success was based on the quantitative levels of estradiol on a specific day in down-regulated cycle. RESULTS The overall pregnancy rate was 32.25 % (50/160). Estradiol level on down-regulated day 2 was 31.9 ± 12.6 and on the day of trigger was 1,996.46 ± 1,252.36 in pregnant women, which was significantly higher as compared to estradiol levels in non-pregnant women (27.6 ± 12.3 and 1,525.1 ± 1,116.42, respectively). It was found to be a significant prognostic marker for successful IVF treatment. Estradiol levels on down-regulated day 6 were found to be non-significant between the two groups. CONCLUSIONS Estradiol level on down-regulated day 2 of menstrual cycle and on the day of trigger was found to have a significant impact on the success of IVF-ET.