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

The corpus luteum plays a crucial role in the menstrual cycle by producing progesterone, which is essential for preparing the endometrium, or uterine lining, for potential implantation of a fertilized egg. After ovulation, when an egg is released from the ovary, the structure that remains in the ovary is the corpus luteum. Its primary function is to secrete progesterone, which increases the blood supply to the endometrium and promotes the thickening and maintenance of the uterine lining. If pregnancy occurs, this progesterone production is vital for sustaining the early stages of pregnancy until the placenta can take over hormone production.

Without sufficient progesterone from the corpus luteum, the endometrium would not be adequately prepared to support a fertilized egg, leading to potential miscarriage or failure of implantation. This role highlights the significance of the corpus luteum in the reproductive process, making its function a critical component of the menstrual cycle. Thus, option B accurately describes its role in supporting any potential pregnancy.