Serum estradiol concentrations as a predictor of successful outcome in artificial frozen-thawed embryo transfer cycles

Abhilasha N. Tomar, Vaibhav N. Nadkarni, Jigna S. Garasia, Purnima K. Nadkarni


Background: The role of late follicular serum estradiol monitoring in artificial FET cycles remain unclear. The purpose of this study was to evaluate the correlation between serum estradiol levels on the day of starting progesterone supplementation with clinical pregnancy rates in FET cycle.

Methods: This was a non-interventional observational cohort study of patients undergoing ICSI followed by FET at Nadkarni hospital and test tube baby center, Killa-Pardi, Gujarat during the period of January 2021 to May 2021. Total 64 cycles were studied and serum estradiol levels were analyzed on the day of starting progesterone supplementation. They were divided into 3 groups based on serum E2 levels (0-25th centile, 25th-75th centile and >75th centile). Chi square/Fisher exact test were used to compare the clinical pregnancy and implantation rates between these groups.

Results: Clinical pregnancy and implantation rates in group A, B and C were 68.8%, 78.1%, 75% and 36.98±9.06, 32.03±4.48 and 29.69±5.69 respectively.

Conclusions: Serum estradiol levels before progesterone supplementation in FET cycles do not predict the outcome of FET cycle therefore making routine monitoring of serum estradiol in FET cycle of questionable value.


Estradiol, FET, ICSI, Pregnancy

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