Which structure is responsible for producing progestin hormones necessary for maintaining pregnancy?

The corpus luteum is the structure responsible for producing progestin hormones, particularly progesterone, which is crucial for maintaining pregnancy. After ovulation, the follicle transforms into the corpus luteum, which secretes progesterone. This hormone is essential for preparing the endometrium (the lining of the uterus) for potential implantation of a fertilized egg. It stabilizes the uterine environment, preventing contractions that could lead to the expulsion of the developing embryo and supports early gestation by inhibiting further ovulation during pregnancy.

While the ovaries do produce hormones, including progesterone, they also produce other hormones and are not specifically responsible for sustaining a pregnancy after ovulation. The placenta, which forms later in pregnancy, takes over hormone production but is not present at the very start when the corpus luteum is primarily active. Similarly, the endometrium plays a supportive role during pregnancy by providing an appropriate environment for implantation and nurturing the embryo, but it does not produce hormones necessary to maintain pregnancy on its own. Thus, the corpus luteum is specifically recognized for its role in producing the required progestin hormones during the early stages of pregnancy.