Irregular Periods: Why Is My Period Irregular?

Irregular periods are a menstrual cycle disorder in which periods occur too frequently or too infrequently, or where the duration or heaviness of bleeding consistently differs from the usual cycle. Typically, the menstrual cycle lasts between 21 and 35 days, and periods last between 4 and 7 days. Although a 28-day cycle is often mentioned, every woman’s body is unique, so slight variations in the cycle are normal. Irregular periods can be caused by hormonal imbalances, stress, certain illnesses, medication, lifestyle changes or other factors.

When are periods considered irregular?

Periods occur more frequently than every 21 days or less frequently than every 35 days;
There are no periods for 3 or more consecutive months;
Bleeding is unusually heavy or very light;
Periods last longer than 7 days;
The length of the cycle consistently varies by more than 7–9 days;
There is bleeding between periods or after sexual intercourse;
Periods are accompanied by severe pain, nausea or vomiting;
You have to change a sanitary towel or tampon more than once an hour.

What are the conditions associated with irregular periods?

Amenorrhoea: the absence of periods for more than 90 days, not due to pregnancy, breastfeeding or the menopause;
Oligomenorrhoea: infrequent periods, where the cycle lasts longer than 35 days or there are fewer than 8 periods per year;
Dysmenorrhoea: painful periods accompanied by severe abdominal cramps and discomfort;
Abnormal uterine bleeding: this includes bleeding between periods, very heavy periods or prolonged periods.

The most common causes of irregular periods

Endometriosis: a chronic, progressive condition in which tissue similar to the inner lining of the womb grows outside the uterine cavity and causes a chronic, oestrogen-dependent inflammatory reaction;
Pelvic inflammatory disease: an infection caused by microorganisms that ascend from the vagina and cervix to the upper reproductive organs – the uterus, fallopian tubes, pelvic peritoneum and other adjacent organs;
Polycystic ovary syndrome: a hormonal imbalance associated with increased androgen production by the ovaries and accompanied by biochemical and metabolic changes;
Primary ovarian insufficiency: a disorder of ovarian function occurring before the age of 40, resulting in infrequent or completely absent menstruation;
Thyroid or pituitary disorders: hypothyroidism (underactive thyroid), hyperthyroidism (overactive thyroid) and other thyroid or pituitary disorders affect hormonal balance. As a result, periods become irregular;
Bleeding disorders: certain blood clotting disorders can cause heavy or prolonged menstrual bleeding;
Cancer of the uterus or ovaries: in some cases, changes in menstruation may be associated with benign or malignant changes in the reproductive system.

The impact of lifestyle on the menstrual cycle

The regularity of periods can be affected by:

Constant stress;
Sudden weight loss or gain;
Intense physical exertion;
Poor nutrition;
Acute or chronic illnesses;
Lack of sleep.

Other possible causes

Pregnancy;
Breastfeeding;
Miscarriage;
Ectopic pregnancy;
Hormonal contraception;
Certain medicines (e.g. steroids, blood-thinning medication);
Surgery or scarring of the uterus.

How are irregular periods diagnosed?

Medical history and gynaecological examination: to diagnose irregular periods, the doctor will ask about troublesome symptoms and past illnesses, and will carry out a gynaecological examination of the abdomen and pelvis;
Genetic testing: this may be recommended if primary ovarian insufficiency is suspected, particularly in women under 40;
Ultrasound scan: this helps to identify uterine fibroids, polyps, ovarian cysts and other structural abnormalities.
Magnetic resonance imaging (MRI) or computed tomography (CT): performed in more complex cases where a detailed assessment of changes in the pelvic organs is required or to confirm the diagnosis;
Hysteroscopy: a procedure that allows the doctor to examine and assess changes in the uterine cavity and carry out interventions;
Endometrial biopsy: performed to assess the condition of the endometrium and rule out precancerous or malignant changes.

How are irregular periods treated?

Medication

Hormonal contraceptives – help regulate the menstrual cycle, reduce bleeding and control hormonal imbalances;
Tranexamic acid – prescribed to reduce heavy menstrual bleeding;
Non-steroidal anti-inflammatory drugs (NSAIDs) – help to reduce pain and cramps during menstruation;
Hormone therapy – may be used during the perimenopausal period or in cases of hormone deficiency;
Antibacterial treatment – if an infection is the cause of irregular periods, you may be prescribed antibiotics;
Gonadotropin-releasing hormone (GnRH) agonists: may be used to treat uterine fibroids and heavy bleeding.

Surgical treatment

Endometrial ablation – this is a procedure in which the lining of the womb is reduced or destroyed in order to reduce bleeding.
Myomectomy is a surgical procedure designed to remove uterine fibroids, which are the cause of irregular bleeding;
Uterine artery embolisation: a procedure that reduces the blood supply to the uterus in order to halt the growth of uterine fibroids;
Hysterectomy – an operation to remove the uterus, used only in certain complex cases.

How can you reduce the risk of irregular periods?

Maintain a healthy body weight;
Eat a balanced diet;
Exercise regularly;
Get enough rest;
Learn to manage stress;
Use contraceptives as recommended by your doctor;
Have regular check-ups.

When should you be concerned and see a doctor about vaginal discharge?

You have not had a period for more than 3 months;
Bleeding is very heavy;
Your period lasts longer than 7 days;
You are bleeding between periods or after the menopause;
Your periods are accompanied by severe pain;
Your discharge has an unpleasant odour;
You experience nausea, vomiting or a fever.

FAQs

Is it normal for periods to be 1–2 months late?

Sometimes your period can be affected by stress, weight changes, intense exercise or a change in hormonal contraception. However, if you haven’t had a period for more than 3 months, you should consult a doctor.

How long is it normal for a period to be late?

Fluctuations of a few days in your cycle are normal. If your cycle suddenly becomes very irregular or its duration changes significantly, it is recommended that you have a gynaecological examination.