Menstrual Cycle: Phases, Hormones, and Endometrium

Notes

The Menstrual Cycle The menstrual cycle The menstrual cycle is the monthly series of changes a woman's body goes through in preparation for the possibility of pregnancy. Can range from 27-31 days MENSTRUAL CYCLE • Menstrual cycle-lasts about 28 days but varies in length between 25 and 35 days. • one egg is produced per cycle. • Lining of uterus is made ready to accept embryo that will grow in the uterus if the egg is fertilized. • Involves a synchronized recurring changes in the lining of the uterus (endometrium) of a non- pregnant women. • Begins as an ovum (egg) matures inside a follicle in an ovary. From day 1 – day 5 Uterine lining (endometrium) breaks down & passes out with the unfertilized ovum This period is called menstruation From day 6 – day 13 The uterine lining builds up again which is induced by female sex hormone. The hormone responsible for the build up of the uterine lining is oestrogen Day 14 Ovulation occurs Ovulation is the release of a mature egg From day 15 – day 28 The uterine lining remains thick and spongy Thickened uterine lining is ready to receive a fertilized ovum Menstrual Cycle Ovary From day 1 – day 13 Follicle is developing until mature Ovulation Aft...