Progesterone does far more than support pregnancy — it’s the hidden hormone shaping every phase of your cycle.
Written by Madeleine Leek, DO, during her fourth year of medical school as part of the FACTS elective, this article explores a narrative review on progesterone’s central role in fertility, implantation, and early pregnancy. From basal body temperature shifts to changes in cervical mucus, Dr. Leek breaks down how this single hormone drives the biomarkers that fertility awareness-based methods (FABMs) rely on every day.
In this piece, you’ll learn:
- How progesterone transforms the endometrium after ovulation — and why that matters for implantation
- Why post-ovulatory temperature rises and changes in cervical mucus are direct signals of progesterone at work
- How luteal phase defects show up on FABM charts and what they may signal about fertility or early pregnancy loss
- Why the method of progesterone supplementation (vaginal, intramuscular, or oral) affects how it’s metabolized and absorbed
- Where future research is headed, including better endometrial receptivity markers and the role of lifestyle factors like stress and sleep
Whether you’re charting your cycle for family planning or trying to better understand your hormonal health, this review offers a science-backed look at why progesterone deserves more attention than it often gets.
Want to learn more? Read the full article on FACTS About Fertility.
