corpus luteumThe female reproductive system is entirely internal.The vagina is the canal that leads from the outside of the body to the cervix, the opening to the uterus.
|>>||Follicle stimulating hormone ( FSH)|
|>>||Luteinising hormones ( LH)|
As these hormones are released, the monthly menstrual cycle occurs in three phases:
PHASES OF THE MENSTRUAL CYCLE
This begins on day 1 of the menstrual cycle, the first day of menstrual bleeding. FSH begins by stimulating the development of many follicles, but as levels of FSH gradually fall in a natural cycle only one follicle will dominate & go on to produces a mature egg. The non-dominant follicles are absorbed by the ovary & cannot be used again. The developing follicle also secretes estrogen, which has several functions. For example, estrogen develops the watery mid-cycle changes in cervical mucus that assist the passage of sperm into the uterus & also causes the thickening of the endometrium required for implantation. The main estrogen the ovary produces is estradiol.
This phase is short. It begins when, in response to rising estrogen levels, the level of LH rises dramatically. This LH surge triggers final maturation of the egg.The rupture of the follicle & then the release of the eggs. This usually happens 14 days before the next period is due or on day 14 of a 28-day cycle.
Begins after ovulation, at this point, the ovarian follicle where the egg developed collapses & solidified to become the corpus luteum