Causes & Treatment

How common are IVF mix-ups in the UK?

Jessie Day, Senior Editor  |   5 Jan 2024

In short, extremely rare. Learnings from decades-old incidents have required the UK to put in place stringent check processes and frameworks, to ensure in vitro mix up likelihood is all-but zero. All-but – so not impossible, but extremely unlikely. 

Your clinic should be able to run you through these rigorous checking requirements, any time you ask. But recent headlines covering a heartbreaking embryo implantation error in California, USA, have triggered understandable renewed concerns. 

So, how common are IVF mix-ups UK-wise, in 2024? Let’s dig in. 

The Toft Report, 2004

But first, let’s rewind, to 2002. 

In July of that year, Sir Liam Donaldson, Chief Medical Officer for England at the time, commissioned Professor Brian Toft to investigate circumstances surrounding the sperm mix-up – alongside three other incidents – occurring at assisted reproduction units in the Leeds Teaching Hospitals NHS Trust, West Yorkshire. 

In this case, two couples arrived on the same day, for treatment at the same facility. Human error, however, heartbreakingly led to a sperm mix-up, with the samples being switched. It was only on the birth of twins to Mr and Mrs A that the error became clear. The twins were mixed race, and the couple were both white. 

Key findings and takeaways from Toft’s Report, published in 2004, included serious concerns regarding: 

  • human error 
  • poor management
  • systems failures

His report made over 100 recommendations for change, heavily criticised fertility services in the UK, the government itself, and the governing body – the Human Fertilisation and Embryology Authority (HFEA). 

HFEA, government and services – crucial learnings

Today, the HFEA is an iron rod across UK fertility services, NHS or otherwise. But in 2004, as the Toft Report published, it was accused of operating within a culture of secrecy, alongside other more specific accusations around management and inspection procedure. 

The government was also called out on its inadequate funding of the HFEA, alongside clinics and fertility services themselves, for understaffing and lacking facilities. 

Crucially, Professor Toft made it clear in his report that since the incidents at Leeds NHS Trust, improvements had already been made. And in a statement, the HFEA welcomed the recommendations, having already put in place 85 per cent of Toft’s recommendations, before the report was published. 

The sector – and industry – had learned, at huge personal cost to an unknown number of families. But, what sort of picture are we looking at today?

mistakes in implanting embryos

A witnessing framework, for every clinic

One of the HFEA’s landmark changes, following the Toft Report, was implementing a stringent witnessing framework. Going forward, as part of the HFEA Code of Practice, every clinic – NHS or private – would be required to use the framework, designed to ensure granular, meticulous checking across every stage of the IVF process. 

You can read the very latest HFEA Code of Practice here, along with any previous versions. 

And while witnessing, and assuring patient and donor identification, makes up one crucial part of the Code of Practice, UK patients also benefit from strict governance around all of the following thanks to its reach, including: 

  • regulatory principles
  • staffing and personnel 
  • counselling and patient support
  • consent
  • legal parenthood
  • multiple births
  • child welfare
  • embryo and PGT-A testing, and sex selection 
  • donor conception, mitochondrial donation, egg sharing and surrogacy
  • gamete and embryo transport and storage
  • traceability
  • research and training
  • quality management systems
  • third parties 
  • premises, practices and facilities 
  • equipment and materials 
  • adverse incidents 
  • complaints
  • treating people fairly
  • confidentiality and privacy
  • record keeping and document control
  • reporting requirements

In an interview this week published in The Telegraph, Director of Compliance & Information at the HFEA, Rachel Cutting, says “The UK is really the only place that has absolutely formal, highly regulated IVF”.

This is in the context of recent headlines around mix-ups in the US, adding that, the events preceding the Toff Report in the UK in 2002 triggered many crucial learnings and changes,

“That was then the witnessing guidance was really strengthened […] In the code practice, every time you collect eggs, you collect sperm, you prepare sperm, you change tubes, you move embryos, you transfer something – everything is always double witnessed.”

Talking numbers – how common are IVF mistakes?

In its State of the fertility sector 2022/23 report, published in September 2023, the HFEA noted the following key findings, taken from 85 inspections across 2022-23: 

  • critical non-compliances have decreased to 2%
  • no Grade A incidents since 2020/21
  • severe/critical OHSS incidents consistent with previous years 
  • patient complaints decreased

What’s a ‘Grade A’ incident?

A Grade A, at the HFEA, is the most serious type of reported incident amongst the licenced clinics it regulates. In its report (see above), the HFEA notes that: 

  • around 100,000 treatment and storage cycles are carried out each year, as well as 1,200 new egg donor registrations
  • over 99% of these are carried out with no incident reported 
  • of those incidents, very few are Grade A 

Reporting incidents is a statutory requirement. Getting more granular, the HFEA notes that in 2022/23: 

  • 517 incidents and 89 ‘near misses’ were reported to the HFEA
  • just over half of all of these were Grade C, with the remainder being Grade B
  • there were no Grade A incidents from 2020/21 to 2022/23

In summary, IVF mix-ups in the UK are extremely rare, largely due to learnings from past incidents occurring over the last two decades, and stringent processes put in place as a result – plus, an overhaul of the HFEA’S funding and set-up. 

Your to-do list

Keen to learn more? The HFEA is packed with information, which you can cross-check with your clinic or treatment provider if you’re unsure. Let us know too, if you have a question or query – we’re super-quick to respond in our Insta DMs. 

Read next – Switching fertility clinics – the top 5 reasons patients move their treatment, and how to go about it

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