A 25 year old woman presents with a change to her periods. She is experiencing heavy, painful bleeding for the first time. Which of the following is the least appropriate investigation?

A) Urine beta-HCG
B) FBC
C) Serum free testosterone
D) TSH
E) LH/FSH ratio


The answer is E.

Pregnancy test should be performed in all women of childbearing age who present with heavy bleeding. FBC is used to account for the blood loss and discern if anaemia is present. TSH is used to diagnose hypothyroidism (hyperthyroidism results in loss of periods). LH/FSH ratio is used to diagnose polycystic ovary syndrome which presents with irregular periods, rather than heavy, painful periods.