Somewhere in your IVF journey, usually after a cycle has not worked, someone will offer you an extra. It will have a name that sounds scientific, a price that is not small, and a hope attached. That is an add-on.
As a GP, I read the evidence for these for a living. As a patient, I know what it feels like to be offered one when you are tired and grieving and would pay almost anything to change the next result. This article is the calm version of that conversation, written before you need it.
What counts as an IVF add-on?
The Human Fertilisation and Embryology Authority (HFEA), which regulates every UK clinic, defines add-ons as optional extra treatments, tests or technologies offered on top of standard IVF or ICSI, usually at extra cost, and usually with the claim that they improve your chances. Commonly offered examples include:
- Endometrial scratching
- Time-lapse imaging of embryos
- Pre-implantation genetic testing for aneuploidy (PGT-A)
- Embryo glue (hyaluronate-enriched transfer medium)
- Assisted hatching
- Immunological tests and treatments, including intralipid infusions and steroids
- Sperm selection techniques such as PICSI or IMSI
- ICSI when there is no male-factor problem
- Endometrial receptivity testing
Prices range from under a hundred pounds to several thousand per cycle.
How the HFEA rates them
Since October 2023 the HFEA has used a five-colour rating for each add-on, based on the best available evidence for people having routine IVF. In plain words:
- Green: good evidence that it improves the chance of a live birth for most patients.
- Amber: the evidence conflicts. It might help; it might not.
- Grey: not enough evidence to say either way.
- Black: good evidence that it makes no difference to live birth rates.
- Red: evidence that it may reduce your chances, or raise safety concerns.
When the new ratings launched, no add-on was rated green. Most sat in grey, amber or black. The ratings are updated as evidence arrives, so rather than list them here and go out of date, I will point you to the source: the HFEA treatment add-ons page. Look up each one you are offered. It takes two minutes.
In June 2026 a large review, widely reported in the UK press, reached the same conclusion the HFEA has been signalling for years: most add-ons sold to improve IVF success have no proven effect on live birth rates.
Why clinics offer them anyway
Not, in most cases, out of cynicism. Clinics are under pressure from patients who have read about a technique online and want it. Some add-ons make sense for specific groups even when they do not help the general population. And some clinicians genuinely believe in a technique ahead of the evidence, which is how medicine has always moved, for better and worse.
But add-ons are also revenue, and the person offering one is rarely a neutral party. Both things can be true. Your job is to ask the questions that separate them.
Six questions to ask before you pay for any add-on
- What is the HFEA rating for this, today? If the clinician does not know, that is a data point.
- What is the evidence for people like me? Some add-ons have a rationale for a specific problem (for example, a sperm selection technique for a specific sperm abnormality) and none for anyone else. "Like me" means my age, my diagnosis, my history.
- What would it change? Ask for the absolute difference: not "improves outcomes" but "raises the live birth chance from roughly X to roughly Y for someone like you". If there is no number, there is no evidence.
- What are the risks? Every intervention has some. A biopsy for genetic testing is a procedure on an embryo. Steroids have side effects. Ask.
- What does it cost, and is that per cycle or per embryo? Then ask what else that money could buy: another cycle, for instance.
- Can I take this away and decide? The answer should always be yes. Consent given in the moment, under pressure, is not the standard the HFEA expects.
When an add-on may be reasonable
I am not against every add-on. There are situations where one is defensible:
- There is a specific, tested reason in your case that the technique addresses.
- Your clinician can show you the evidence for that situation, not the general population.
- You understand the cost and the risk, you have had time to think, and you would make the same choice tomorrow.
- You are choosing it with clear eyes, not as a way to feel you have done everything.
That last one matters. Grief looks for action. Sometimes the most protective thing you can do for yourself is to spend the money on the next cycle, or on counselling, or on nothing at all.
What I tell patients
Standard IVF, done well, at a clinic with good verified results, with a single embryo transferred, is the evidence-based package. Almost everything sold on top is uncertain at best. If you are going to spend more, spend it on the things that reliably move the numbers: not smoking, a healthy weight, the right dose of folic acid, and the number of good-quality embryos you can make and transfer over time.
The full evidence walk-through for private testing, add-ons, supplements and how to read a clinic's numbers is in Fertility Foundations, the audio programme I built for exactly the conversation you are about to have. And if you are preparing for the appointment where these will be offered, take questions to ask at your first fertility clinic appointment with you.
Sources: HFEA: treatment add-ons; HFEA: improved ratings for treatment add-ons (2023); The Guardian, June 2026: most IVF add-on treatments have no effect.