Clomifene citrate

How it works

It blocks hypothalamic oestrogen receptors, reducing negative feedback and increasing pituitary release of follicle-stimulating and luteinising hormones to stimulate follicular development and ovulation.

Prescribing in practice

• Multiple pregnancy risk is increased, so use the lowest effective dose and counsel the patient about this before starting.
• Treatment should be restricted to a limited number of cycles because of uncertainty about ovarian effects with prolonged use, and given under specialist or appropriately supervised care.
• It is contraindicated in pregnancy, liver disease and undiagnosed abnormal uterine bleeding, which must be investigated first.

Monitoring

Monitor ovulatory response and follicular development, typically with cycle tracking or ultrasound, and limit the number of treatment cycles.

Counselling the patient

• Be aware of the higher chance of twins or other multiple pregnancy.
• Report visual disturbances such as blurring or flashes, and stop the drug until reviewed.
• Seek urgent advice for severe abdominal pain or bloating, which may signal ovarian hyperstimulation.

Evidence & guidelines

Clomifene citrate is a long-standing first-line ovulation induction agent, with NICE recognising it among the options for women with polycystic ovary syndrome-related anovulation.