Menstrual Cycle


Menstrual Cycle

  1. Menstruation: Breakdown of the lining of uterine wall and its discharge through the vagina, with small amount of blood and cell
  2. Menstrual cycle:
  • A monthly cycle, consisting of follicle development,ovulation,thickening of the endometrium and menstruation
  • 28 days for each cycle

       3. Importance of menstrual cycle:

  • Prepares the uterine lining for the implantation of an embryo
  • Controls the development of ovum and ovulation
The hormones involved in controlling menstrual cycle :
Hormone Functions Effects
Follicle stimulating hormone (FSH)

• Stimulates follicle development in the ovaries

• Stimulates oestrogen secretion by the follicles

Control the changes in the ovaries
Luteinening hormone

• Stimulates ovulation

• Causes the formation of the corpus luteum

• Promotes the secretion of progesterone

Control the changes in the ovaries

• Repair and revival of of endometrium after menstruation 

• Stimulates FSH and LH secretion before ovulation

Control the changes in the uterus

• Stimulates the endometrium to become thick,folded and highly vasculated for embryo development

• Inhibits FSH and LH secretion

Control the changes in the uterus
Events of the menstrual cycle:
Time (days) In the ovary In the uterus
0-5 Follicle develops Menstruation
6-13 Follicle matures Endometrium repaired, thickens
14 Ovulation Endometrium continues to thicken
15-24 Corpus luteum develops Tissue and blood vessels develop in the endometrium
25-28 Corpus luteum degenerates as no fertilisation occur Endometrium will begin to disintegrate after 28th day


Premenstrual syndrome (PMS):
  • Headache
  • Breast swelling and pain
  • Stomach pain
  • Muscle or joint pain
  • Feeling tired
  • Sleep problems
  • Bloating
  • Food cravings
  • Constipation
  • Trouble with concentration or memory
  • Anxiety
  • Irritable
  • Tension
  • Depression
  • Crying spells
  • Mood swings
Menopause syndrome:
  • Occurs between 46 till 54 years old
  • Ovary is less sensitive to the stimulation of FSH and LH
  • No follicle developed and no ovum formed
  • low production of progesterone and oestrogen
  • Hot flashes
  • Sleep problems
  • Urinary problems
  • Vaginal problems and infections
  • Osteoporosis
  • Irregular periods
  • Night sweats
  • Weight gains
  • Memory problems
  • Mood swings
  • Depression
  • Anxiety