In IVF cycles, the luteal phase is shorter compared to the natural cycle. This is due to the variation in supraphysiological progesterone and estradiol levels of the early luteal phase, induced by the hCG trigger. Progesterone significantly reduces the production of luteinizing hormone (LH) via negative feedback mechanisms on the hypothalamus and pituitary. As LH activity is crucial for the function of the corpus luteum, the significant reduction of this gonadotropin will result in corpus luteum malfunction. This necessitates luteal phase support at least until pregnancy is well detected, 12 -14 days after the embryo transfer.
Thus, the early luteal progesterone profile in IVF differs markedly from the progesterone profile of the natural, unstimulated cycle, in which the peak of progesterone is reached around 6-8 days after ovulation: the time of expected implantation. In contrast, the premature early luteal phase rise in progesterone appears after the ovarian stimulation, with exogenous gonadotropins and the hCG trigger, advancing the window of implantation. This may cause asynchrony between the embryo and the endometrium, which may result in implantation failure and poor reproductive outcomes.
This Research Topic aims to contribute to the identification of the ideal luteal phase support during assisted reproduction. Ideally, luteal phase support should be associated with high implantation, clinical and ongoing pregnancy rates, no increased risk of ovarian hyperstimulation syndrome, and should be well tolerated by patients.
Furthermore, it may differ in various fertility treatments, including controlled ovarian stimulation, fresh IVF cycles (including different stimulation protocols), frozen-thawed cycles, egg donations, etc. We welcome topical submissions related to the above-mentioned areas, considering all article types, with Original Research, Reviews, and Systematic Reviews, being particularly welcome.
In IVF cycles, the luteal phase is shorter compared to the natural cycle. This is due to the variation in supraphysiological progesterone and estradiol levels of the early luteal phase, induced by the hCG trigger. Progesterone significantly reduces the production of luteinizing hormone (LH) via negative feedback mechanisms on the hypothalamus and pituitary. As LH activity is crucial for the function of the corpus luteum, the significant reduction of this gonadotropin will result in corpus luteum malfunction. This necessitates luteal phase support at least until pregnancy is well detected, 12 -14 days after the embryo transfer.
Thus, the early luteal progesterone profile in IVF differs markedly from the progesterone profile of the natural, unstimulated cycle, in which the peak of progesterone is reached around 6-8 days after ovulation: the time of expected implantation. In contrast, the premature early luteal phase rise in progesterone appears after the ovarian stimulation, with exogenous gonadotropins and the hCG trigger, advancing the window of implantation. This may cause asynchrony between the embryo and the endometrium, which may result in implantation failure and poor reproductive outcomes.
This Research Topic aims to contribute to the identification of the ideal luteal phase support during assisted reproduction. Ideally, luteal phase support should be associated with high implantation, clinical and ongoing pregnancy rates, no increased risk of ovarian hyperstimulation syndrome, and should be well tolerated by patients.
Furthermore, it may differ in various fertility treatments, including controlled ovarian stimulation, fresh IVF cycles (including different stimulation protocols), frozen-thawed cycles, egg donations, etc. We welcome topical submissions related to the above-mentioned areas, considering all article types, with Original Research, Reviews, and Systematic Reviews, being particularly welcome.
