Why are gonadotrophins used in IVF?

Gonadotrophins are medicines that act like hormones involved in follicle growth. In an IVF cycle, they encourage more than one follicle to develop, rather than relying on the single-follicle pattern of an unmedicated cycle. The aim is to provide eggs for the next laboratory steps, while ultrasound scans and blood tests show how the ovaries are responding.

The dose is individualised and can change as monitoring information becomes available. Other medicines may be used to control ovulation and coordinate egg collection. Learn more about [Gonadotrophins](/materials/gonadotrophins/) and [IVF](/treatments/fertility-and-assisted-reproduction/ivf/).

Inject the medicine exactly as taught and attend every scheduled monitoring appointment. Mild bruising or soreness can occur at injection sites. Keep a record of doses and report medicines, supplements, allergies, or symptoms that could affect the plan.

Do not change the amount or timing because a follicle measurement looks different from what you expected. If you miss an injection, call the IVF team promptly so they can explain the next step.

Tell the IVF team about worsening abdominal swelling, pelvic discomfort, nausea, vomiting, or rapid changes in how you feel. Seek urgent help for severe pain, trouble breathing, fainting, heavy bleeding, or very little urine. Prompt review helps the team identify and manage a strong ovarian response or another urgent problem.

Ask what the gonadotrophin is expected to do, how scans and blood tests will guide the dose, and when egg collection is likely to be planned. Clarify injection technique, missed-dose instructions, warning symptoms, and the clinic's after-hours contact.