Progesterone in HRT-FET cycles: a game of hide and seek.

Graphical AbstractOpen in new tabDownload slideThe February ESHRE Journal Club discussion focused on a study by Maignien et al. (2022), the novel clinical variables accounting for low progesterone levels on day of FET in patients undergoing HRT and the difficulties of defining an ideal luteal phase support in these patients. FET: frozen embryo transfer; HRT: hormone replacement therapy; P4: progesterone.