Menstrual cycle

• Menstrual cycle


  The monthly cycle that gets the body ready for a potential pregnancy
• The menstrual cycle lasts around 28 days, but it can vary slightly from individual to individual
• Female reproductive system


  • Ovaries - where eggs mature
  • Uterus - where the fetus develops
  • Cervix - entrance to the uterus
  • Vagina - receives sperm during sexual intercourse
  • Fallopian tubes - where the egg is fertilized and travels to the uterus
• Menstrual cycle


  1. Uterus lining thickens to be ready for potential pregnancy

  2. An egg matures in one of the ovaries

  3. Egg is released from the ovary (ovulation)

  4. Egg travels down the fallopian tube

  5. If egg is fertilized, it implants in the uterus lining

  6. If egg is not fertilized, the uterus lining is shed (menstruation)
• Hormones involved in the menstrual cycle

  • Follicle Stimulating Hormone (FSH) - stimulates egg maturation and estrogen production
  • Estrogen - thickens the uterus lining
  • Luteinizing Hormone (LH) - triggers ovulation
  • Progesterone - maintains the uterus lining
• Hormones involved in the menstrual cycle

  • Follicle Stimulating Hormone (FSH)
  • Estrogen
  • Luteinizing Hormone (LH)
  • Progesterone
• Follicle Stimulating Hormone (FSH)


  Secreted by the pituitary gland, travels to the ovaries and causes an egg to mature, also stimulates the ovaries to produce estrogen
• Estrogen


  Produced and secreted by the ovaries, causes the uterus lining to thicken, inhibits the production of FSH
• Luteinizing Hormone (LH)


  Secreted by the pituitary gland, triggers ovulation
• Progesterone


  Maintains the uterus lining, inhibits the production of LH, remains high during pregnancy
• Menstrual cycle graph


  • Graph 1: FSH and LH levels
  • Graph 2: Estrogen levels
  • Graph 3: Progesterone levels
  • Graph 4: Uterus lining thickness
• FSH increases


  Egg matures, ovaries produce estrogen, uterus lining thickens
• Estrogen increases


  Uterus lining thickens
• Progesterone is high


  Uterus lining is maintained
• Progesterone decreases


  Uterus lining breaks down (menstruation)