A 20-year-old Indian presents with primary amenorrhoea with normal secondary sexual characteristics. Discuss how you will manage this patient.

Primary amenorrhoea is defined as the absence of menstruation by 16 years of age or the failure to develop secondary characteristics by 14 years of age. The pathology can lie in the hypothalamus, pituitary, ovary and reproductive outflow tract. 

Since the patient has normal secondary sexual characteristics, it implies that puberty has occurred, stimulated by the gonadotrophins and estrogen and therefore it is quite unlikely that the problem lies at the hypothalamus, pituitary or ovaries causing insufficient production of the sex hormones. In this case, the presentation of primary amenorrhoea with normal second sexual characteristics should raise the possibility of congenital absence of the vagina as the primary concern until proven otherwise. 

A detailed history is essential to formulate a correct diagnosis:

1.	Developmental history.

2.	Presence or absence of cyclical symptoms: abdominal pain. 

3.	History of chronic illness.

4.	Excessive weight loss / presence of an eating disorder: a minimum of 17% of ideal body weight is required to initiate and maintain menses.

5.	Excessive exercise.

Though the following conditions are unlikely, they are asked for completeness’ sake.

6.	Galactorrhoea: hyperprolactaemia.

7.	History or family history of anosmia: Kallman’s syndrome. 

8.	Visual disturbances or defects: craniopharyngioma. 

Physical examination

1.	Height, weight and BMI.

2.	Visual field defect.

3.	Stigmata of chromosomal disorders.

4.	Blood pressure.

5.	External genitalia.

6.	Outflow tract abnormalities.

7.	Adnexal masses.

Investigations

1.	Gonadotrophin level: to exclude any hypothalamus / pituitary causes.

2.	Thyroid function tests.

3.	Ultrasound of pelvis to detect outflow tract abnormalities. 

It is highly likely that the cause of the primary amenorrhoea is due to one of the following outflow tract abnormalities:

1.	Mullerian agenesis: congenital absence of vagina or uterus or both.

2.	Transverse vaginal septum: results from an embryological failure of the lower third of the vagina to canalize.

3.	Imperforate hymen: results from an absent orifice in the vaginal hymen, which remains asymptomatic until puberty. 

4.	Vaginal atresia.

Management

1.	Vaginal atresia: use of graduated glass dilators to stretch the small vagina into a fully functional vagina or using surgery to create a vagina.

2.	Imperforate hymen: a cruciate incision to release the menstrual blood. 

3.	Transverse vaginal septum: surgery to correct the absent portion by its excision and reconstruction of the vagina.