What is the role of the corpus luteum in the menstrual cycle?

The corpus luteum plays a crucial role in the menstrual cycle, particularly after ovulation. After the follicle releases an egg, it transforms into the corpus luteum. This structure is essential because it secretes hormones, primarily progesterone and some estrogen, which are vital for maintaining the uterine lining.

If pregnancy occurs, these hormones support the environment necessary for a fertilized egg to implant and help sustain the early stages of pregnancy. The corpus luteum continues to function and release hormones until the placenta takes over hormone production. If pregnancy does not occur, the corpus luteum eventually degenerates, leading to a decrease in hormone levels and triggering menstruation. This highlights why the correct answer emphasizes the corpus luteum's function in hormone secretion to maintain pregnancy.

The other options do not accurately represent the primary role of the corpus luteum in the menstrual cycle. Functions like accelerating ovulation, facilitating follicle development, or eliminating waste products do not pertain to the specific actions of the corpus luteum during this phase.