Heavy periods are defined by a flow that requires the highest absorbency tampon or pad that must be changed sooner than recommended—usually within an hour.

The reasons women have heavy periods include:

• The natural flow is just heavy
• Use of the birth control method called an IUD (intra-uterine device)
• "Hormonal imbalance" (too little or no progesterone)
• Fibroids or polyps (growths that sometimes occur in the uterus)
• Thyroid problems (the thyroid is a gland in the neck that helps control many body functions)
• Endometriosis—a condition in which cells from the lining of the uterus travel and grow in other parts of the body
• Cigarette smoking
• Childbirth (Many women have heavy flow during the first year or so after childbirth.)
• Some of these conditions don’t need to be treated. Others may require treatment.

When to see a doctor about heavy periods
If you have a normally heavy period, there is usually no need for concern. However, you should see a doctor if:

• You feel tired all the time: Very heavy periods may cause anaemia, which is a deficiency of the red blood cells that carry oxygen around the body. If you feel physically drained, ask a doctor to check for anemia.

• You experience "flooding" (leaking through a super absorbency pad or tampon within one hour): If your periods get heavy and change in consistency, you should see a doctor. If no medical reasons are found for heavy flow, the doctor may prescribe oral contraceptives, or use cyclical progesterone to regulate the periods.