Gonadotrophins (injectable fertility hormones)

What gonadotrophins do

Gonadotrophins are injectable hormones based on follicle-stimulating hormone (FSH) activity, sometimes with luteinising hormone (LH) activity. They stimulate the ovaries to develop several eggs during treatments such as IVF and egg freezing, and are sometimes used to induce ovulation. They are always used with monitoring so your clinic can adjust care to your response.

Safety and monitoring

Because these medicines increase ovarian activity, clinics monitor with ultrasound scans — often alongside blood estradiol tests — and watch for ovarian hyperstimulation syndrome (OHSS). The HFEA notes that about a third of people get mild OHSS, which is usually managed at home, while severe OHSS is uncommon but occasionally serious. Warning signs to report include severe abdominal pain and swelling, nausea or vomiting, breathlessness, faintness, and reduced urine output, typically in the week after egg collection.

This page does not provide dosing. Follow the exact instructions from your own clinic and the current product information (SmPC) for your specific medicine. Never adjust doses, timing, or stopping without your clinic’s guidance.