Dysfunctional Uterine Bleeding

Key facts

• Dysfunctional uterine bleeding (DUB) is abnormal bleeding from the uterus with no obvious structural cause: no fibroids, polyps, or pregnancy involved.
• It is driven by hormonal imbalance, usually a disruption in the normal oestrogen-progesterone cycle, and can make periods too heavy, too long, too frequent, or unpredictable.
• It is most common at the two hormonal extremes of reproductive life: adolescence and perimenopause, often linked to cycles where ovulation does not occur.
• Progestogens such as medroxyprogesterone are the main hormonal treatment, used to stabilise the uterine lining and reduce abnormal bleeding.

Why the cycle goes off balance

DUB is most common at the two hormonal extremes of reproductive life: adolescence, when the cycle is still becoming regular, and perimenopause, when ovarian function begins to fluctuate. Anovulatory cycles, where ovulation does not occur, are a frequent driver. Without ovulation, progesterone is not produced in the usual amounts, so oestrogen keeps stimulating the uterine lining unchecked until it sheds irregularly and often heavily. Stress, significant weight change, and thyroid disorders can all push the cycle into anovulation, and ruling these out is part of a standard assessment before treatment begins.

Regulating the bleed

Hormonal therapy is the main approach to dysfunctional uterine bleeding. Progestogens are commonly used to counterbalance oestrogen and bring the cycle back under control. Medroxyprogesterone is one such option, used to stabilise the endometrium and reduce abnormal bleeding. Treatment is usually given for several cycles, and many women see their bleeding pattern settle within a few months. Broader support for conditions like DUB sits within women's health care, and a doctor will typically want to confirm the diagnosis with blood tests or a pelvic scan before starting hormonal treatment, since DUB is essentially a diagnosis of exclusion.

When to see a doctor

Heavy or prolonged bleeding that soaks through protection rapidly, or bleeding accompanied by severe pain or dizziness, warrants prompt medical review.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.