Why is my period so heavy? Common causes and what helps
Heavy periods are often caused by hormone shifts that thicken the uterine lining (common in teens, perimenopause and PCOS), or by fibroids, polyps, adenomyosis, endometriosis, a copper IUD or a bleeding disorder. Sometimes no cause is found. One heavy period can happen, but heavy bleeding every cycle is common and treatable, so it's worth seeing a doctor.
Common causes of heavy periods
| Cause | Clues |
|---|---|
| Hormone imbalance | Irregular cycles, often in teens, perimenopause or PCOS. Without ovulation, the lining builds up and sheds heavily |
| Fibroids | Heavy, long periods, pelvic pressure, needing to pee often; common in 30s and 40s |
| Polyps | Heavy periods or bleeding between periods |
| Adenomyosis | Heavy, painful periods, often in your 40s |
| Endometriosis | Painful periods, pain with sex, sometimes heavy flow |
| Copper IUD | Heavier, longer periods, especially in the first months |
| Bleeding disorders | Heavy periods since your first period, easy bruising, nosebleeds, heavy bleeding after dental work |
| Thyroid problems | Heavy or irregular periods with tiredness or weight changes |
| Some medicines | Blood thinners can make periods heavier |
| Pregnancy complications | Heavy bleeding after a late period: get checked promptly |
If this is just one unusually heavy period, a late ovulation (or no ovulation that cycle) is a common reason: the lining had longer to build. If it's every cycle, it's worth finding the cause. See heavy periods for the full guide and what counts as a heavy period to check if yours is.
Signs your period is heavy
- Soaking a pad or tampon every 1 to 2 hours for several hours
- Needing to double up protection, or change at night
- Clots the size of a quarter (about 2.5 cm) or bigger
- Bleeding for more than 7 days
- Feeling tired, breathless or dizzy, which can mean anemia
- Planning your life around your period
What helps
Treatment depends on the cause, but there are good options. Anti-inflammatory painkillers like ibuprofen taken during your period can reduce flow as well as pain. Tranexamic acid helps blood clot and can cut flow a lot. The hormonal IUD is one of the most effective treatments, and combined pills or progestogen tablets help many people. Iron supplements treat anemia. Fibroids and polyps can be removed if needed.
Heavy periods are draining in every sense. Low iron makes tiredness and low mood worse, and many people feel anxious around leaks. If your period week leaves you exhausted, it's not just you, and it's worth raising. See tired on your period.
See a doctor if heavy periods affect your daily life, if you pass large clots, if bleeding lasts more than 7 days, or if you feel tired, breathless or dizzy. Get urgent help if you soak a pad an hour for more than 2 hours, feel faint, or are bleeding heavily and could be pregnant.
Frequently asked questions
Why is my period suddenly so heavy?
A sudden heavy period can follow a delayed ovulation, stress, a new IUD or medicine, or a very early miscarriage. If it repeats, see a doctor.
Can stress make your period heavier?
Stress can disrupt ovulation, which can lead to a heavier, later period. Ongoing heavy bleeding has other causes worth checking.
Do heavy periods get worse with age?
They often do in your 40s, as perimenopause and conditions like fibroids become more common. See perimenopause periods.
Can heavy periods cause anemia?
Yes. Iron-deficiency anemia is a common result of heavy periods. A simple blood test can check.
Sources
- NHS: Heavy periods
- ACOG: Heavy Menstrual Bleeding
- NICE guideline NG88: Heavy menstrual bleeding: assessment and management
- Cleveland Clinic: Menorrhagia (heavy menstrual bleeding)
This page is for information only and isn鈥檛 medical advice. If something worries you, please talk to a doctor.
Keep reading
Heavy periods: what counts as heavy and what helpsHow to tell if you have heavy periods: soaking a pad every hour or two, clots, bleeding over 7 days. Causes, treatments that work, and when to get help.What counts as a heavy period?What is a heavy period? Soaking a pad or tampon every 1 to 2 hours, clots bigger than a quarter, or bleeding over 7 days. A quick self-check.
Are blood clots normal during your period?Are blood clots normal during your period? Small ones usually are. Why clots form, what size is too big, and when clots are a sign to see a doctor.
Adenomyosis: symptoms, diagnosis and what helpsAdenomyosis explained: heavy, painful periods and a tender, bulky uterus. Who it affects, how it differs from endometriosis, diagnosis and treatment.
Period calculator: when is my next period?Free period calculator: enter the first day of your last period and your cycle length to see your next 6 periods. Private, instant, nothing is stored.
Perimenopause periods: what's normal and what isn'tPerimenopause periods can come closer together, skip, flood or barely show. What's typical at each stage, coping with heavy bleeding, and when to get checked.