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Beyond the uterine first pass: optimizing programmed frozen embryo transfers. A mini-review
Ryszard J Chetkowski1, Sofia Gaggiotti-Marre2
1Alta Bates In Vitro Fertilization Program, Berkeley, California.
F&S Reports
|September 23, 2021
Summary
Progesterone replacement in programmed cycles for IVF and frozen embryo transfers is being reevaluated. Combined vaginal and intramuscular progesterone offers a more physiologic approach than monotherapy, improving endometrial and serum levels.
Area of Science:
- Reproductive endocrinology and infertility treatments.
Background:
- Segmented in vitro fertilization (IVF) and frozen embryo transfers (FETs) are increasingly popular.
- Current progesterone replacement strategies in programmed cycles require reexamination.
Purpose of the Study:
- To reevaluate progesterone replacement strategies in programmed cycles for IVF and FETs.
- To explain the disconnect between endometrial and serum progesterone levels with monotherapy.
Main Methods:
- The study discusses bidirectionality and uterine first-pass metabolism of progesterone.
- It contrasts monotherapy (vaginal or intramuscular) with combined therapy.
Main Results:
- Vaginal or intramuscular progesterone monotherapy alone can lead to disconnects between endometrial and serum levels.
- Combined progesterone therapy addresses these disconnects.
Conclusions:
- Monotherapy with progesterone deviates from the natural hormonal profile of spontaneous pregnancies.
- Combined progesterone therapy provides a more physiologic replacement strategy.
- Combined therapy minimizes the number of injections required.
