Irregular Periods and Bleeding
Irregular periods and abnormal uterine bleeding occur when your menstrual cycle changes from its usual pattern. This may include periods that are too frequent, too far apart, unusually heavy, very light, or bleeding that occurs between periods. While occasional changes can be normal, persistent irregular bleeding should be assessed.
Commonality
Causes
Irregular periods can occur for many reasons, ranging from temporary hormonal changes to underlying medical conditions.
Common causes include:
Thyroid disorders
Stress
Significant weight loss or weight gain
Excessive exercise
Changes in hormonal contraception
Pregnancy-related bleeding
Bleeding disorders
Symptoms
Symptoms may include:
Periods occurring more frequently than every 21 days
Cycles longer than 35 days
Missed periods
Bleeding between periods
Bleeding after sex
Very heavy or prolonged periods
Unpredictable cycle length
Persistent spotting
Sudden heavy bleeding
Pelvic pain
Unusual vaginal discharge
Fatigue or symptoms of anaemia
Effects on Fertility
Diagnosis
Diagnosis usually begins with a detailed review of symptoms, menstrual history and medical background.
Investigations may include:
Medical history and cycle review
Pelvic examination
Pelvic ultrasound scan
Blood tests to assess hormone levels, thyroid function and markers associated with PCOS
Pregnancy testing when appropriate
Endometrial biopsy in selected cases of persistent abnormal bleeding
These investigations help identify the underlying cause and guide treatment.
Treatments
Treatment depends on the cause of the irregular bleeding and individual preferences.
Lifestyle measures may include:
Stress management
Nutritional optimisation
Maintaining a healthy weight
Adjusting exercise levels
Hormonal treatments may include:
Combined oral contraceptive pill
Progestogen therapies
Hormonal intrauterine system (such as the Mirena coil)
Targeted medical treatment may be required for underlying conditions such as:
Thyroid disorders
Surgical treatment may be considered for structural causes such as:
Modern minimally invasive techniques are often used where appropriate.
Ongoing Care
Living with the Condition
Irregular periods can affect both physical and emotional wellbeing. Unpredictable bleeding may create anxiety, inconvenience and disruption to daily life, work and social activities.
Understanding the cause of abnormal bleeding can provide reassurance, and in most cases symptoms can be effectively managed once the underlying issue is identified.
When to See a Specialist
You should seek specialist assessment if you experience:
Sudden changes in your menstrual cycle
Bleeding between periods
Bleeding after sex
Very heavy bleeding
Repeated missed periods that are not related to pregnancy
Pelvic pain or unusual discharge
Fatigue or symptoms of anaemia
Early assessment can help identify the cause, provide reassurance and allow treatment to begin sooner.