Menstrual cycle it is controlled by sex hormones which are responsible for the onset of secondary sexual characteristics and also control of the menstrual cycle. The onset is signaled by discharge of blood/menses 14 days following the start of menstruation. Anterior lobe of pituitary gland secretes follicle stimulating honnone(FSH).
1. Follicle stimulating hormone causes graafian follicle to develop in the ovary. It also stimulates tissues of the ovary/wall (theca) to secrete oestrogen
2. Oestrogen causes repair/healing of uterine wall also oestrogen stimulates anterior lobe of pituitary to produce luteinising hormonge (LH)
3. LH causes ovulation. It also causes graafian follicle to change into corpus luteum. LH stimulates corpus luteum to secrete progesterone
4. Oesterogen/progesterone inhibits, the production of FSH by anterior lobe of pituitary, thus no more follicles develop and oestrogen production reduces
In the next two weeks progesterone level rises and inhibits production of LH from anterior lobe of pituitary“
The corpus lutetium stops secreting progesterone and menstruation occurs when the level of progesterone drops. Anterior lobe of pituitary starts secreting FSH again.