ovarian cycle

• • Fsh stimulates development and maturation of egg in follicle
• • Follicle containing maturing egg secretes estrogen causing changes in lining of uterine wall (endometrium)
• • Lining of uterine wall becomes thicker, softer and spongy and richly supplied with blood vessels in readiness to receive fertilised egg
• • Peak in eastern levels trigger increase in LH triggering ovulation
• • Ovulation is release of mature egg from ruptured follicle into fallopian tube (oviduct) where it can become fertilised by sperm 
• • Left behind in the ovary, the burst follicle is called corpus luteum. LH stimulates corpus luteum to secrete progesterone and some oestrogen to cause further thickening of uterine wall for implantation of fertilised egg
• 1. If egg is fertilised, moves into uterus and implants into uterine wall
• Egg not fertilized, passes out of reproductive tract and corpus luteum slowly disintegrates and stops releasing hormones causing thickened uterine wall to break down and menstruation occurs