Irregular bleeding
What counts as a normal period, when irregular bleeding needs investigating, the causes at each stage of life, and how it is diagnosed and treated.
Abnormal uterine bleeding is a common gynaecological complaint affecting women at every age. After puberty, menstrual cycles generally follow a pattern of bleeding lasting fewer than seven days, in cycles of between 24 and 38 days. Bleeding outside these limits is called abnormal uterine bleeding.
What a normal period looks like
- Frequency: every 24-38 days
- Duration: 4-8 days
- Volume: 4-80 ml
When to see a doctor
- bleeding heavy enough to soak through a pad or tampon every hour or more often
- needing to use two sanitary pads at once to control the bleeding
- needing to change a pad during the night
- a period lasting longer than seven days
- bleeding containing large clots
- heavy bleeding that affects normal life
- continuous pain or cramping in the lower abdomen during a period
- less than 24 days or more than 38 days between periods
- bleeding between regular periods
- tiredness, exhaustion or breathlessness (signs of anaemia)
Causes by stage of life
Childhood
Bleeding before the first period must be investigated. In this age group the most common causes are vulvovaginitis (genital infection), skin conditions, tumours, or trauma from an accident, misuse or a foreign body. As well as vaginal bleeding, bleeding can arise from the urinary tract, and prolapse and infection should be looked for. True uterine bleeding arises from a raised oestrogen level, and early puberty, accidental hormone use or ovarian tumours should be investigated.
Adolescence
In adolescence, abnormal uterine bleeding occurs at higher rates than in women of reproductive age, arising from ovulation disorders and from problems with blood clotting.
Reproductive age
Abnormal uterine bleeding is a frequent problem in women of reproductive age. It is estimated that one woman in twenty will consult a doctor about irregular bleeding at some point in her life. With increasing sexual activity, bleeding related to pregnancy and sexually transmitted infections becomes more common. Fibroids and polyps of the endometrium (the lining of the womb) become more frequent with age, and bleeding from these lesions is common in older women of reproductive age. Isthmocele — a condition that has gained attention in recent years, seen in women who have had a caesarean section — can also cause abnormal uterine bleeding.
Perimenopause
Abnormal uterine bleeding is a frequent clinical problem, accounting for 70% of gynaecological consultations in women during the transition to the menopause and afterwards. Irregular bleeding from disordered ovulation is common at this stage, while bleeding related to pregnancy and sexually transmitted infections decreases. With increasing age the risk of both benign (non-cancerous) and malignant (cancerous) tumours rises. In one study, precancerous lesions or cancer were found in 18% of women presenting with irregular bleeding at this stage.
After the menopause
Bleeding after the menopause is not normal and must always be investigated. Although harmless causes are usually found — thinning of the womb lining, a polyp, infection — cancer must be excluded. Ulcers on the external genital area and cancers of the vagina and cervix can also cause bleeding, as can bleeding from the rectum, vagina or urethra. Establishing where the bleeding comes from is therefore important.
Bleeding after sex
Bleeding after intercourse is most often seen in women between 20 and 40. Cervical eversion (from hormonal change or use of the contraceptive pill), an endocervical polyp, cervical infection and changes in the cervix related to HPV are the common causes at this stage.
How it is diagnosed
- pelvic examination
- examination of the cervix
- a smear test
- a pregnancy test, if you have not reached the menopause
- blood tests to check how your blood clots and for a full blood count
- thyroid tests (problems with thyroid function can also be a sign of a problem with ovarian function)
- hormone levels
- hysteroscopy — viewing the inside of the womb with a camera, examining the lining for fibroids, polyps or signs of cancer
- pelvic ultrasound
- a biopsy of the womb lining, recommended for women over 35, those with a family history, and those carrying risk factors for cancer
How it is treated
The method used depends on the woman's age, on whether she wishes to have children and on the underlying cause.
Medical treatment may be used — hormones, the contraceptive pill, progestins, anti-inflammatory painkillers, tranexamic acid, a hormonal coil — and in some situations surgical treatment: hysteroscopic removal of a polyp or fibroid, ablation, treatment of an isthmocele, myomectomy or hysterectomy. Treatment is therefore individualised.
See also irregular periods.