Lawfully running a red light: a response from the HFEA

In last week's BioNews, Julian Hitchcock argued that a recent statement from the Human Fertilisation and Embryology Authority (HFEA) on embryo selection needed clarification (see BioNews 1134). I am happy to do that today.

Our statement was given to the Times in response to an article on the trend in the USA for clinics to screen embryos using polygenic risk scores (so-called PGT-P). It was a short press statement and not the place for a detailed analysis or response.

Given the aim of PGT-P, we focused on the fact that PGT-P is currently unlawful in the UK, and to comment on the purposes for which PGT-M or PGT-SR can be used. We used the umbrella term 'embryo selection' because that is most straightforward to the lay reader.

Hitchcock is quite right to argue that PGT-A does not fit this model, so let me take this opportunity to set the record straight.

PGT-A is lawful under the Human Fertilisation and Embryology Act 1990 (as amended), which allows embryo testing for a range of purposes including establishing whether an embryo has a chromosome abnormality that may affect its capacity to result in a live birth. One of the claims made for PGT-A is that it reduces the chances of miscarriage in some women, but there have been a number of studies in recent years disputing this (see BioNews 962, 1097 and 1123).

The HFEA first agreed the use of PGT-A in 2001 for specific subsets of patients only. After monitoring the evidence base, in 2008 the Authority agreed that the Code of Practice should be updated to expand the use of PGT-A to potentially any patient. However, patients should be informed of the technique's experimental nature and the need for more clinical trials. This guidance remains in the current Code (in Guidance note 9). Although the techniques used to undertake PGT-A may have changed over the last 20 years, it is still being used to test for the same genetic anomaly that it was first approved for by the HFEA in 2001.

Our central issue with PGT-A is not is it lawful, but does it work? And this is a question we have asked not just of PGT-A, but also of several other 'treatment add-ons'. The HFEA's traffic light rated list of add-ons is a resource that we have created for patients to help them interpret the often complex evidence base for these treatments. It is designed to be a simple and clear way to aid patients in making an informed decision about whether to use an add-on as part of their fertility treatment. We make that assessment on the basis of whether the evidence (in the form of randomised controlled studies) indicates that a treatment can increase the live birth rate for most fertility patients. The rating system is not an indication of whether a process is authorised for use within HFEA licensed clinics.

The article also raises questions about the regulation of tests and medical devices. The HFEA regulates that part of the PGT-A service carried out in the licensed clinic (information provision, consent, treatment, biopsy). The clinic itself must have a third-party contract with the laboratory undertaking the testing, and an HFEA licence condition requires that laboratory to meet the appropriate accredited standards.

Our traffic light ratings were not introduced as a regulatory tool, and Hitchcock is right to note that clinicians can offer PGT-A if they judge it to be an appropriate treatment option based on a patient's individual medical history. On our traffic light web page we acknowledge that some add-ons may be suitable to use in some patients for varying reasons, such as to decrease the chance of miscarriage. In 2019, the most recent validated figures we have, PGT-A cycles made up just 0.27 percent of total fresh embryo transfers and 4.29 percent of frozen embryo transfers in IVF/ICSI in the UK. While its usage is increasing, we are still a very long way away from the kind of routine offering of PGT-A that we see in the USA, where 37.7 percent of IVF transfers involve embryos which have been screened using PGT-A.