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Updated: Nov 8, 2025

Methods for Studying Uterine Contributions to Pregnancy Establishment in an Ovariectomized Mouse Model
Published on: April 7, 2023
New concepts and difficulties with progesterone supplementation in the luteal phase
María Cerrillo Martínez1, Cristina Rodríguez-Varela2, Elena Labarta Demur2,3
1IVIRMA, Madrid.
Purpose Of Review:
Management of the luteal phase (LP) in assisted reproductive cycles has aroused interest in recent years. The reason is that it seems that the individualization of LP support may be necessary, since the concept of 'one size fits all' does not apply to this treatment.
Recent Findings:
Studies carried out in hormone replacement therapy cycles (also called artificial cycles) have shown that serum levels of progesterone (P) are related to pregnancy outcomes. This represents a milestone in the management of artificial cycles (AC), because until a few years ago it was believed that serum levels did not really reflect the effectiveness of P, which is why they were neglected. However, it is not as straightforward as it seems, because the interpretation of serum progesterone values will depend on the type of progesterone used and its route of administration. Likewise, the findings observed in AC are not applicable to what occurs in a fresh transfer cycle after ovarian stimulation or an embryo transfer in the context of a natural cycle.
Summary:
In this manuscript, we will summarize the current situation in LP management.
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