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
Menstrual cycle of the menstrual cycle, regardless of fertility. Behavior towards potential mating partners changes during different phases of the menstrual cycle. Near ovulation, women may have increased physical attraction and interest in attending social gatherings with men. During the fertile phase of the cycle, women appear to prefer males who are more masculine. The intensity of mate guarding differs across the phases of the cycle, with increased mate guarding occurring when woman are fertile. During the fertile phase, many women experience more attraction, fantasies and sexual interest for extra pair men but not for the primary partner. They also engage in