Physiology of Menstruation

PHASES

Menstruation is a complex process. For better understanding it can be classified in different ways.

On the basis of changes that occur in the ovaries

  1. Follicular phase or the phase before ovulation.
  2. Ovulatory phase or the phase of ovulation
  3. Postovulatory (Luteal) phase or the phase after ovulation.

On the basis of changes that take place in the linings of the uterus

  1. Proliferative phase.
  2. Ovulatory phase.
  3. Secretory phase.
  4. Menstrual phase

The time interval between ovulation and the onset of menstruation is constantly close to 14 days for all women (normal range is 12-17 days).

Mechanisms of Menstruation
Hormonal Regulation
Prostaglandins