Heavy Periods: How to Tell If Yours Are Too Heavy, and When to Get Checked

Changing a pad every hour, passing large clots or feeling exhausted may mean heavy menstrual bleeding. Here is how to tell, the common causes and the treatments that work.

The short answer

A period is considered heavy when the bleeding affects your daily life. Signs include soaking a pad or tampon every one to two hours, needing to double up protection, bleeding through to clothes or bedding, clots bigger than a 25-cent coin, or a period lasting more than seven days. Heavy bleeding is common, treatable, and a leading cause of low iron in women.

Signs your period may be too heavy

• Changing a pad, tampon or cup every 1 to 2 hours for several hours in a row
• Getting up at night to change protection
• Using two products at once, or avoiding plans because of flooding
• Clots about 2.5 cm across or larger
• Bleeding for more than 7 days
• Tiredness, shortness of breath or feeling faint, which can mean iron-deficiency anaemia

Common causes

• Hormone shifts in the teen years and perimenopause, when ovulation is irregular
• Fibroids or polyps in the uterus
• Adenomyosis, when lining tissue grows into the uterine muscle
• Copper IUD, which can make periods heavier
• Bleeding disorders such as von Willebrand disease, especially if heavy periods began with your first period or you bruise or bleed easily
• Thyroid problems and some medicines, including blood thinners

Often no single cause is found, and treatment still helps.

What a doctor may check

Expect questions about your cycle and symptoms, and possibly a pelvic exam, a blood count and ferritin (iron stores), a thyroid test, a pregnancy test and a pelvic ultrasound. If bleeding has been heavy since your first period, ask about testing for a bleeding disorder.

Treatments that work

• Hormonal IUD (levonorgestrel), one of the most effective options, often making periods much lighter
• Tranexamic acid tablets taken only on heavy days to help blood clot
• NSAIDs such as ibuprofen or naproxen, which reduce both bleeding and pain
• Combined pill, patch or ring, or progestin-only options
• Procedures such as polyp or fibroid removal, endometrial ablation or, when other options fail and family is complete, hysterectomy
• Iron replacement if your iron is low

When to seek care urgently

Go to emergency care if you soak through a pad an hour for more than two hours with dizziness, a racing heart or fainting, or if you could be pregnant. Book a regular appointment for any of the signs above, bleeding between periods or after sex, or bleeding after menopause.

Frequently asked questions