MENSTRUAL CYCLE

• Menstrual cycle


  Monthly cycle in which the uterus prepares for pregnancy in women aged 12-50
• Menstruation


  First stage of cycle, lasts 3-7 days, uterine lining is expelled
• Ovulation


  Second stage, when woman is most fertile, egg is released from ovary
• Egg is fertilized and embeds

  Menstruation does not occur, woman becomes pregnant
• Egg is not fertilized

  Uterine lining breaks down, menstruation occurs, cycle repeats
• Estrogen


  Hormone produced by ovaries, causes uterine lining to thicken after menstruation
• Progesterone


  Hormone produced by empty follicle, maintains uterine lining if egg is fertilized
• Follicle stimulating hormone (FSH)


  Secreted by pituitary gland, causes egg to mature and stimulates ovaries to release estrogen
• Luteinizing hormone (LH)


  Secreted by pituitary gland, causes mature egg to be released and stimulates progesterone release
• Estrogen builds up the uterus lining, progesterone maintains it during second half of cycle
• FSH and LH are involved in controlling the menstrual cycle