A 45-year-old woman presents to the GP with a 4-month history of intermenstrual bleeding and increasingly heavy periods. Pelvic examination reveals a bulky, irregularly enlarged uterus. A pelvic ultrasound shows multiple intramural fibroids, the largest measuring 6 cm. Her haemoglobin is 98 g/L. Which is the single most appropriate initial management while awaiting gynaecology review?