Introduction

Premenstrual syndrome refers to a group of physical and psychological symptoms that occur in there 2-14 days before menstruation, and tend to resolve as soon as menstruation begins.

The exact pathology is not known, but hormonal changes are the underlying reason. The most likely theory is that PMS is a result of increased sensitivity to progesterone, and reduced serotonin levels, often on the background of low serotonin.

For a diagnosis of PMS there should be a symptom-free period in the follicular phase, and an absence of an alternative explanation (typically depression or anxiety or another psychological disorder).

PMS is also different from the normal physiological premenstrual symptoms by the presence of both psychological and physical symptoms.

Premenstrual dysphoric disorder (PMDD) is a more severe form of PMD, with particularly severe psychological symptoms.

Epidemiology

  • More common after age of 30
  • Peak incidence age 30-40
  • Affects up to 50% of women
    • 90% of women experience premenstraul symptoms, but only about 50% severe enough o fall under a diagnosis of PMS
  • PMDD affects 2-5% of women
  • History of PMS increased the likelihood of mood disorder around the time of menopause

Aetiology

Risk factors include:

  • History of mental illness
  • Alcoholism
  • Hysterectomy
  • Tubal ligation
  • Recent cessation of COCP
  • Smoking
  • Life stressors
  • Sedentary lifestyle

Presentation

  • Mental
    • Depression – 70%
    • Irritability – 55%
    • Tiredness – 35%
    • Aggression / violence – 13%
    • Insomnia
    • Food cravings
  • Physical
    • Headache – 30%
    • Bloated – 30%
    • Breast tenderness – 20%
    • Dizziness
    • Nausea
    • Constipation
    • Fluid retention / peripheral oedema

Symptom severity

PMS can be divided into three categories

  • Mild – symptoms do not interfere with personal, social and professional life
  • Moderate – symptoms interfere with life, but patine still able to perform and interact, albeit with reduced performance
  • Severe – patient prevented from normal daily activities, particularly social interaction. Patients often become withdrawn. In most severe cases, symptoms may cause suicidal ideation and suicide attempts

Diagnosis

Diagnosis requires a combination of some of the typical symptoms above, which can be shown to be associated with the menstrual cycle – in the luteal phase – and to completely resolve during the follicular phase.

  • Rule out an underlying psychological disorder
  • Ask patients to keep a menstrual diary along with the frequency and severity of their three main symptoms for at least 3 months

Investigations

Investigations are not typically required. Hormonal assays in particular are not useful. Consider testing to rule out other differentials:

  • TSH
  • U+Es for renal dysfunction that be causing fluid retention

Differential diagnosis

Management

Make sure to treat any other underlying disorders, such as depression, thyroid disorders, or PCOS.

Lifestyle measures

  • Regular exercise
    • At least 30 minutes per day on 5 days of the week
  • Avoiding alcohol
  • Stress reduction techniques – e.g. mindfullness, meditation
  • Cognitive behaviour therapy (typically through referral to psychologist, although self-directed online CBT may also be beneficial – e.g. with ‘Headspace’ app)

Medication

  • SSRIs can help to improve serotonin levels and reduce symptoms
    • May be used continuously, or as a 14 day cycle, starting on day 14 of each menstrual cycle
    • Fluoxetine 20mg OD or Sertraline 50mg OD are recommended
  • COCP can modify hormonal levels and improve symptoms
    • Often best if packets are ‘run together’ to avoid periods of withdrawal
    • This can be done safely for up to 12 months at a time
    • In a minority of women, COCP may aggravate symtpoms
  • NSAIDs may help to relieve physical symptoms – particularly mastalgia (breast pain)
  • Vitamin B6 50-100mg daily
  • Spironolactone
    • Useful if coexisting PCOS or if fluid retention is a significant symptom
  • Other options
    • Calcium and magnesium supplements have been shown to be beneficial
    • Evening primrose oil is not of proven benefit
    • Vitamin E is not proven to be effective

Specialist treatments

  • If the patient does not respond, consider referral to gynaecology
  • Hormone suppression treatments are available, such as:
    • HnRH agonists
    • Estradiol patches, with oral progestin
  • Bilateral oophorectomy may be considered in patients not responsive to these treatments

References

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