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How does the corpus luteum change during early pregnancy?
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human reproductive system
Organs and structures of the male and female reproductive systems.
If fertilization occurs and the blastocyst implants in the uterus, the corpus luteum undergoes significant changes to support the pregnancy rather than degenerating as it would in a non-pregnant cycle.1
The primary changes include:
- Prolonged Lifespan: Cells of the developing blastocyst produce hormones, most notably human chorionic gonadotropin (HCG), which signal the corpus luteum to persist in an active state.12
- Continued Hormone Secretion: The corpus luteum remains active for at least the first two months of pregnancy, continuing to secrete progesterone and estrogens necessary for maintaining the uterine environment.12
- Eventual Regression: Once the placenta has developed sufficiently to take over the production of these hormones, the corpus luteum is no longer required. It then retrogresses and eventually becomes a fibrous scar by the time of parturition.12