Heavy periods and iron deficiency: what the NHS describes

The NHS lists heavy periods as one of the most common causes of iron deficiency anaemia. Periods differ a great deal from person to person, and the NHS says heavy periods are common and can be normal for some people. What matters is whether they affect daily life.

How the NHS describes heavy periods

• Needing to change pads or tampons every one to two hours, or emptying a menstrual cup more often than the maker recommends.
• Needing to use two period products at once.
• Periods that last more than seven days.
• Passing blood clots about the size of a 10p coin or larger.
• Bleeding through to clothes or bedding.
• Avoiding exercise or other daily activities, or taking time off work, because of the bleeding.
• Feeling tired or short of breath often.

Why it connects to iron

Blood contains iron, so losing more blood each month can use up the body’s iron faster than it is replaced. The NHS says doctors may arrange blood tests to check for iron deficiency anaemia when periods are heavy.

Possible reasons for heavy periods

The NHS says heavy periods can be a normal variation, including in the first years of periods, after pregnancy or approaching the menopause. They can also come with conditions of the womb or ovaries such as fibroids or endometriosis, with bleeding disorders, and with some medicines. A doctor can look into the cause.

What helps in an appointment

Heavy bleeding is easier to describe with dates and counts than from memory: the first and last day, how many products you used each day, any flooding or clots, and anything you had to cancel. FerroLady can record bleeding days, and ferrolady.com/guides has a guide to keeping a bleeding diary.