A woman can lose between 5 to 80mL (almost 6tbsp) of blood during a normal period. It’s important to know what’s “normal” for you. That means how often your period happens, how light or heavy it is, and how long it lasts. 

Your period should be about the same length and volume of blood loss each cycle. Periods can fluctuate when you first start menstruating, after pregnancy, and as you approach menopause around the age of 50. Not ovulating regularly  is a common cause of temporarily absent or heavy menstrual periods. If you don’t ovulate, you may miss a period or come later than usual. This can cause the periods to be heavier or lighter and shorter or longer than your normal period. 

Obesity, polycystic ovarian syndrome, hypothyroidism can stop you from ovulating and change your period. The heaviness and length of your period also depend on your hormones, which can fluctuate. Hormones can change temporarily because of things like stress, exercise, diet, or taking an emergency contraception pill (the morning after pill). 

Every period is different, just as everybody is different.  If you notice a change and it lasts more than three months, keep track of the changes and follow-up with your doctor.

With love, 

Dr. Jodie Horton

Sources: https://helloclue.com/articles/cycle-a-z/what's-normal-period-length