CYCLE‑CONTROL MEDICATIONS
Treatments that balance your hormones and keep your cycle on track, helping us prepare your body for the next stage of fertility care.
Medications to control your cycle during treatment
As part of your fertility treatment, you may be prescribed medicines called agonists or antagonists. These help us carefully control your hormones, allowing your cycle to be managed precisely and giving your eggs the best chance to develop.
Some of these medicines work by preventing your body from releasing an egg too soon, while others lower your natural hormone levels so we can guide your treatment more effectively. They’re an important part of preparing for egg collection and ensuring your treatment stays on track.
On this page, we’ve outlined the most commonly used agonist and antagonist medications, explaining what they do, how they’re taken, and what side effects to look out for.
You’ll find your personal schedule and instructions for these medicines in the Care Fertility treatment companion app, Salve. If you’re ever unsure or worried about anything while taking them, our team is only a call or message away.
Ganirelix
Active ingredient: Ganirelix (0.25mg/0.5mL)
Available form: Pre-filled syringe for injection
Ganirelix belongs to a group of medicines called gonadotrophin-releasing hormone antagonists. Ganirelix stops your body from releasing an egg(s) from your ovary prematurely in fertility treatment cycle. When your eggs are ready to be collected, another medicine (trigger) will be given to you that will release them. Ganirelix can also be used to prevent development of ovarian cysts or to reduce the risk of Ovarian Hyperstimulation Syndrome (OHSS) after the egg collection.
Keep in a cool, dry place below 25°C, away from heat and direct sunlight. Always store in the original packaging.
Ganirelix is given as a small injection under the skin of your thigh at the times shown in your Salve schedule. Wash your hands and prepare in a clean area before injecting.
Mild skin reactions at the injection site, headaches, mood changes, hot flushes, or excessive sweating.
See the leaflet in your medication pack for the full list of possible side effects.
Zoladex
Active ingredient: Goserelin (3.6mg)
Available form: Implant
Zoladex is a type of medicine called an LHRH analogue and contains a medicine called goserelin. Zoladex works by reducing the amount of ‘oestrogen’ (a hormone) that is produced by your body. Zoladex use in fertility is ‘off-label’ which means it will have a licence to treat another condition and will have undergone clinical trials for this.
Keep in a cool, dry place below 25°C, away from heat and direct sunlight. Always store in the original packaging.
Your nurse or doctor will inject a small implant under the skin of your stomach every 28 days.
Hot flushes, difficulty sleeping, headaches, vaginal dryness, mood changes, or joint pain. Allergic reactions are rare but require urgent medical attention.
See the leaflet in your medication pack for the full list of possible side effects.
Prostap
Active ingredient: Leuprorelin acetate (3.75mg)
Available form: Injection
Prostap is a type of medicine called an LHRH analogue, and contains a medicine called leuprorelin acetate. In women, Prostap works by reducing the amount of the hormone, oestrogen that is produced by your body. Prostap can be used to treat endometriosis and can prevent cysts forming in your ovaries.
Keep in a cool, dry place below 25°C, away from heat and direct sunlight. Do not refrigerate or freeze. Always store in the original packaging.
Your nurse or doctor will inject Prostap once a month into your arm, thigh, or abdomen.
Hot flushes, headaches, difficulty sleeping, mood changes, vaginal dryness, joint pain, or skin reactions.
See the leaflet in your medication pack for the full list of possible side effects.
Decapeptyl SR
Active ingredient: Triptorelin
Available form: Injection
Decapeptyl SR is a type of medicine called an LHRH analogue, and contains a medicine called triptoreline. In women, Decapeptyl works by reducing the amount of the hormone, oestrogen that is produced by your body and supresses the ovaries. Decapeptyl can be used to treat endometriosis and can prevent cysts forming in your ovaries.
Keep in a cool, dry place below 25°C, away from heat and direct sunlight. Do not refrigerate. Always store in the original packaging.
Your nurse or doctor will give you a monthly injection, usually into your buttock.
Headaches, hot flushes, vaginal dryness, mood changes, joint pain, and mild injection site reactions.
See the leaflet in your medication pack for the full list of possible side effects.
Buserelin (Suprecur)
Active ingredient: Buserelin acetate (5.5mL vial)
Available form: Multidose vial for injection
Buserelin (Suprecur/Suprefact) contains buserelin acetate, which belongs to a group of medicines called gonadotropin releasing hormone analogues. This is a synthetic version of a hormone that occurs naturally in the body. Buserelin works by lowering the production of sex hormones. It can be used to treat infertility and works by stopping the natural production of hormones that control ovulation.
Keep in a cool, dry place below 25°C and in the outer carton to protect from light. Do not refrigerate.
Important information:
- Do not use Buserelin if you are pregnant.
- Do not have unprotected intercourse while taking this medicine.
Buserelin is injected under the skin of your abdomen at the times shown in your Salve schedule.
Hot flushes, headaches, sweating, mood changes, and mild skin reactions at the injection site.
See the leaflet in your medication pack for the full list of possible side effects.
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