Questionnaire/history: Primary amenorrhoea: No established menstruation by the age of 13 years and no secondary sexual characteristics (such as breast development) and no established menstruation by the age of 15 years and normal secondary sexual characteristics? Sexual history and contraception (to exclude pregnancy or a contraceptive cause of amenorrhoea)? Cyclical lower abdominal pain (suggesting haematocolpos caused by a genital tract malformation)? Stress, depression, weight loss, disturbance of perception of weight or shape, level exercise and chronic systemic illness (suggesting hypothalmic dysfunction)? Headache, visual disturbance or galactorrhoea (suggesting prolactinoma)? Age at menarche of mother and sisters (family history of late menarche suggesting constitutional delay of puberty)? Family history of genetic anomalies (eg androgen insensitivity [46XY female])? Secondary amenorrhoea: Cessation of menstruation for 3-6 months in women with previously normal and regular periods? Cessation of menstruation for 6-12 months in women with previous oligomenorrhoea? Physiological cause (eg pregnancy, lactation or menopause (in women 40+ years)? Contraceptive use? - Extended-cycle combined oral contraceptives? - Injectable progesterone? - Implantable etonogestrel [Nexplanon®]? - Levonorgestrel intrauterine system [Mirena®]? Hot flushes and vaginal dryness (suggesting premature ovarian insufficiency [POI] or natural menopause)? Headaches, visual disturbances, or galactorrhoea (suggesting a pituitary tumour)? Acne, hirsutism, and weight gain (suggesting polycystic ovary syndrome [PCOS])? Stress, depression, weight loss, disturbance of perception of weight or shape, level of exercise, and chronic systemic illness (suggesting hypothalamic dysfunction)? Symptoms of thyroid and other endocrine disease? Obstetric or surgical procedures (such as endometrial curettage) that may have resulted in intrauterine adhesions? Chemotherapy and pelvic radiotherapy (which can cause POI)? Cranial radiotherapy, head injury or major obstetric haemorrhage (which can cause hypopituitarism)? Past medical history? Family history? - Cessation of menses before 40 years (suggesting POI)? Current medication? - Antipsychotics, which can cause increased prolactin levels)? - Illicit drugs (eg cocaine and opiates, which can cause hypogonadism)? Drug allergies? Examination: Height? Weight? Body mass index (a high BMI may suggest polycystic ovary syndrome and a low BMI may suggest an eating disorder)? Features of Turner's Syndrome (eg short stature, web neck, shield chest with widely spaced nipples, wide carrying angle and scoliosis)? Features of Cushing's syndrome (eg striae, buffalo hump, significant central obesity, easy bruising, hypertension and proximal muscle weakness)? Hirsutism and acne (suggesting PCOS, especially in those with a high BMI)? Features of thyroid and other endocrine disease? Clitoromegaly if hirsutism is present (including virilization due to possible androgen-secreting tumour)? Galactorrhoea (suggesting raised prolactin)? Haematocolops if there is a history of cyclical lower abdominal pain (separation of the labia revels a bulging, blue-coloured membrane and a pelvic mass may be palpable)? Features of decreased endogenous oestrogen (eg reddened or thin vaginal mucosa or decreased breast development (as a good maker for a decreased ovarian oestrogen production)? Features of androgen insensitivity (absence of axillary and pubic hair with normal breast development, testes may be palpable in the inguinal canal or labia)? Visual fields (if pituitary tumour suspected)? Pelvic examination inappropriate in young girls who are not sexually active, ultrasound to assess pelvic anatomy? Investigations: Pelvic ultrasound (if the presence of a vagina and uterus cannot be confirmed by physical examination or in place of a pelvic examination in young girls who are not sexually active)? Serum prolactin (if the breasts have been examined, delay the blood test for at least 48 hours)? Thyroid-stimulating hormone? Follicle-stimulating hormone and luteinizing hormone? Total testosterone (if there are features of androgen excess)? Management Reference(s): NICE CKS: Amenorrhoea Information for patient/carer(s): Society for Endocrinology: Amenorrhoea