What initial investigations should I consider for a patient presenting with primary amenorrhoea?

Guideline-aligned answer with reasoning, red flags and references. Clinically reviewed by Dr Kola Tytler MBBS CertHE MBA MRCGP.

Posted: 16 August 2025Updated: 16 August 2025 Guideline-Aligned (High Confidence) Clinically Reviewed
Dr Kola Tytler MBBS CertHE MBA MRCGPClinical Lead • iatroX

For a patient presenting with primary amenorrhoea, the initial consideration in primary care is to refer them to secondary care for specialist investigation and management of the underlying cause .

Referral to secondary care should be considered for:

  • Girls who have no secondary sexual characteristics and have not started menstruating by 13 years of age .
  • Girls with normal secondary sexual characteristics who have not started menstruating by 15 years of age .
  • Girls who have not started menstruating 3 years after thelarche (onset of breast development) or 5 years after thelarche if that occurred before the age of 10 .

Earlier referral should be considered if an abnormality is suspected, such as in those with:

  • Abdominal or pelvic pain .
  • Growth retardation .
  • Symptoms and signs of androgen excess (such as hirsutism) or thyroid disease .
  • Galactorrhoea .
  • Suspected genital tract malformation, intracranial tumour (for example, prolactinoma), or chromosomal anomaly (for example, Turner's syndrome or androgen insensitivity) .
  • Suspected eating disorder, which requires immediate referral to a community-based, age-appropriate eating disorder service .

Referral to a gynaecologist, preferably with a special interest in adolescent gynaecology, is appropriate for most girls with primary amenorrhoea . Referral to an endocrinologist is recommended for girls not showing any secondary sexual characteristics by age 13, or those with hyperprolactinaemia, thyroid disease, or features of androgen excess . Explicit UK-based recommendations on primary care management and when to refer are lacking in published literature, with recommendations based on expert opinion due to the specialist nature of required investigations .

Educational content only. Always verify information and use clinical judgement.