What Is A Normal Menstrual Cycle?
Most women have one menstrual cycle every 22 - 35 days. Calculate Day 1 of your cycle as the first day you start bleeding. Day 1 should be the day when the heaviest bleeding occurs. Bleeding should last only 4 - 6 days. Normal blood loss is 10 - 35 ml, or 2 - 7 soaked sanitary pads per cycle. The absolute maximum blood loss during a heavy cycle should be 45 - 60 ml per cycle (9 - 12 soaked sanitary pads). If it exceeds this amount, the woman is at risk of developing iron deficiency anemia.
Normal menstrual blood is dark or brownish, not bright red.
Normal menstrual blood does not clot easily because it:
- Is high in calcium
- Lacks the clotter prothrombin
- Has very low levels of the clotter fibrinogen
A few women have a regular cycle of 18 - 40 days, and if that is consistent, fairly painless, and not excessively heavy or light, then it is considered a normal variation.
Eighty percent of bleeds last three to six days, indicating an ovulatory cycle, during which an egg was released for fertilization.
Bleeds lasting longer than eight days indicate dysfunctional ovaries. The problem could be anovulation, meaning no egg was released by the ovary for fertilization, or inadequate hormones in the second half of the cycle (luteal phase). Progesterone is supposed to be dominant in the second half.
