Fertility treatment add-ons and the HFEA traffic-light ratings

An add-on is an optional test or procedure that a clinic offers alongside standard IVF or ICSI, usually with the claim that it will raise the chance of a pregnancy. They are not part of the core treatment, they are often paid for separately, and some are offered by clinics with a commercial interest in providing them.

The HFEA introduced a traffic-light system so that patients can see at a glance whether the research supports what is being offered. Clinics licensed in the UK are expected to follow the HFEA guidance on how add-ons are presented to patients.

The ratings describe the evidence, not the clinic. The definitions below follow the HFEA wording as shown on its add-ons page.

The HFEA page listed the following add-ons at the time it was retrieved. Ratings can change after committee reviews, so confirm on the HFEA site before relying on this list.

Endometrial scratching illustrates the point. The HFEA gives it a yellow rating for most IVF and ICSI patients because trials disagree, and a grey rating for people with recurrent implantation failure because there is too little evidence. The regulator also describes the procedure as intrusive and potentially painful, with possible bleeding and a small infection risk if cervical infection is present.

Endometrial receptivity testing is rated red because moderate or high-quality evidence suggests it may reduce treatment effectiveness. The HFEA questions whether the test accurately predicts the best time for transfer and whether that time is the same in each cycle. For microbiome testing the rating is grey for all groups, including people with chronic endometritis.

A good clinic will welcome questions. The aim is a decision you understand rather than one made under pressure during a stressful stage of treatment.

• What is the HFEA rating for this add-on for someone like me?

• What evidence does the clinic rely on, and is it from randomised trials?

• Are there any risks to me, the embryo or a baby?

• What is the full cost, including testing, storage and extra visits?

• What happens if I decline: will my treatment be any different?

• Is the add-on offered as part of a research study with ethical oversight?

Because some add-ons cost more than the basic cycle fee, they can strain budgets, and the regulator reminds patients that proven routine treatment is generally effective without them. You are entitled to time to think and to decline. If you feel pressured, you can ask for the discussion in writing and seek a second opinion from another HFEA-licensed clinic.

Ratings are reviewed when new studies are published. A yellow or grey add-on may move to green if good trials confirm benefit, or to black or red if they do not. Some larger trials are still being analysed, so a grey rating can reflect an unanswered question rather than a finding of no benefit.