IVF success rates: to publish or not to publish?

IVF is a subject that triggers deep emotions, particularly in would-be parents desperate for a baby.

Yet the fertility field also has a strong scientific basis, and this “clinical” side of IVF brings to the fore questions about performance. In recent weeks there has been renewed debate about measurement of IVF success rates, whichindicate the number of treatments carried out by a clinic in a particular year, and the number of resultant pregnancies or live births.   

IVF in Australia is a sophisticated and highly competitive industry, and there are differing opinions about whether patients should have access to comparative performance data to help them choose a fertility provider.

There is a well-maintained record of IVF outcomes and trends, published by the Australian and New Zealand Assisted Reproductive Database (ANZARD) which provides an overall annual report of fertility trends and outcomes.

The latest report, Assisted Reproductive Technology in Australia and New Zealand 2012 showed the live delivery rate from 40,000 fresh IVF treatments at 35 fertility centres that performed at least 90 fresh treatment cycles ranged from 4 per cent at some clinics to 30.9 per cent at other clinics.

Some of the biggest IVF providers have recently called for the publication of success rate data. They argue that there is a large gap between the best performing and worst performing clinics, and that patients - and taxpayers who help fund IVF through Medicare rebates - should have an objective picture of “success rates”.

IVF providers in Australia are members of the Fertility Society of Australia and its current policy is not to publish performance information.

With the current situation, fertility providers use their own data and some couple this with information taken selectively from ANZARD, to demonstrate their “superior” success rates, and publish this on their websites.

League tables are complex, and a fair and accurate comparison must take into account individual patient factors, including cases where patients move to smaller, specialist clinics after numerous IVF failures with large providers.

One of the most influential factors affecting IVF success rates is female age. When presenting pregnancy rates from an IVF unit it is critical to make allowance for the age of the patients. There are several ways of doing this. One can quote the average or median age of the patients or break down the results for certain age ranges, for example, under-35s, over 40s, and so on. The higher the proportion of ‘older’ patients having treatment, the lower the apparent pregnancy rates will be.

The way data is presented can also skew “success”. Some providers quote pregnancy rates only for patients whose embryos have survived to day 5, eliminating poor prognosis patients whose embryos may not reach the day 5 stage. If one was to calculate the pregnancy rate according to the numbers of cycles initiated (i.e. including the patients whose embryos did not reach day 5) the success rate would be much lower.

Overseas, there are a range of approaches to publication of success rates. In the UK, the British Human Fertilisation and Embryology Authority (HFEA) publish annual data for all clinics, but warns against a ‘league table’ approach to success rates, arguing that success rates can be affected by the type of patients treated by clinics, and individual treatments and practices.

Whether patients rely on IVF providers’ websites, or whether in future in Australia success rates are made publicly available, these reports should only be used as one piece of useful information.

Every patient is different. Factors such as female age, cause and duration of infertility and the number of previous unsuccessful cycles all have an impact on whether fertility treatment, including IVF, results in the birth of a healthy baby.

Fertility medicine is a complex area, and over-simplifying “success rates” in marketing material should be approached with caution. As a medical community we need to keep the patient at the centre of our minds at all times.