Menstrual cycle and the lining of the uterus thickens. Follicles in the ovary begin developing under the influence of a complex interplay of hormones, and after several days one or occasionally two become dominant (non-dominant follicles shrink and die). Approximately mid-cycle, 24–36 hours after the luteinizing hormone (LH) surges, the dominant follicle releases an ovocyte, in an event called ovulation. After ovulation, the ovocyte only lives for 24 hours or less without fertilization while the remains of the dominant follicle in the ovary become a corpus luteum; this body has a primary function of producing large amounts of progesterone. Under the influence
Progesterone vaginal ring Progesterone vaginal ring Progesterone vaginal ring, also known as progesterone-only vaginal ring, is a form of vaginal ring used for birth control when breastfeeding. Use can begin at four weeks and continue for at least up to a year following childbirth. Failure rates with usual use is about 1.5 per 100 women. It is used within the vagina with one ring lasting three months. The woman is able to place and remove the ring herself. Side effects include vaginal discharge and pain with urination. It does not appear to be associated with serious side effects. With use menstrual periods often