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How does the corpus luteum help maintain early pregnancy?

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A series of medical illustrations showing the stages of childbirth: the baby's position at the onset of labor, flexion, internal rotation of the head, extension, external rotation of the head, and the uterus immediately after birth with the placenta and umbilical cord. — birth Sequential changes in the position of the child during labour.

The corpus luteum plays a vital role in maintaining early pregnancy by secreting progesterone and estrogens.21

Progesterone is essential for preparing the uterus to support a pregnancy. It stimulates the endometrium to facilitate the implantation and nourishment of the embryo. Furthermore, progesterone inhibits muscular contractions of the uterus that could otherwise lead to the rejection of the implanted egg.213

If fertilization occurs, the developing blastocyst produces hormones, such as human chorionic gonadotropin, which signal the corpus luteum to remain active. It continues to function for at least the first two months of pregnancy, providing the necessary hormonal support until the placenta is sufficiently developed to take over hormone production. Once the placenta assumes this role, the corpus luteum eventually regresses into a fibrous scar.1