Irregular, heavy or painful periods: causes
A normal cycle is usually 24–38 days, with bleeding lasting up to 8 days. Periods that fall outside this, or that are very heavy or painful, are worth investigating.
Common causes
- 01Pregnancy (always rule this out first if a period is late)
- 02PCOS (irregular cycles, acne, excess hair)
- 03Thyroid disorders
- 04Stress, low body weight, under-eating or heavy exercise
- 05Fibroids or endometriosis (heavy or very painful periods)
What a doctor may check
A pregnancy test first. A doctor may check hormones and thyroid, and do an ultrasound.
When to see a doctor
See a doctor for very heavy bleeding (soaking a pad or tampon every hour), bleeding between periods or after sex, or severe pain. For painful periods, anti-inflammatory painkillers work for most women.
This page is general information, not a diagnosis. Venva's content is written against clinical guidelines and systematic reviews, listed below. See our medical disclaimer.
References
- 1.Recommendations from the 2023 International Evidence-based Guideline for PCOS. Journal of Clinical Endocrinology & Metabolism, 2023.doi:10.1210/clinem/dgad463
- 2.The two FIGO systems for normal and abnormal uterine bleeding symptoms. International Journal of Gynecology & Obstetrics, 2018.doi:10.1002/ijgo.12666
- 3.Nonsteroidal anti-inflammatory drugs for dysmenorrhoea. Cochrane Database of Systematic Reviews, 2015.doi:10.1002/14651858.CD001751.pub3
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