IVF success rates are now almost indistinguishable between clinics so patients need to take other factors into account, the regulator says.
The HFEA is launching a new website providing patients with detailed information on every UK clinic, from waiting times to multiple birth rates.
But it will not include data on cost, or mishaps like embryo mix-ups.
For the first time the predicted chance of a fertility clinic delivering a baby based on key factors will be given.
The number of IVF treatments continues to rise. For women under 42 the success rates are up.
But for those aged 43 and above the already low success rate fell again between 2006 and 2007, the last year for which figures are available.
Predicting babies
The website - Choose a Fertility Clinic - will allow would-be patients to examine details of the diagnosis, age and length of infertility of those typically treated at the clinic.
For the first time, it will give a prediction of the chances of a live birth based on a range of factors.
Traditionally statistics have failed to differentiate between a small clinic where three out of 10 patients have delivered a baby and a larger one where 30 out of 100 have done so.
Both have a nominal success rate of 30%, but if the smaller clinic delivers one more baby the rate jumps to 40%, while for the larger clinic it rises by just 0.7%. A new way of displaying data will enable patients to gain a more accurate picture of success rates.
It will also allow them to search for clinics providing specialist services such as pre-genetic diagnosis, PGD. New legislation coming into force on Thursday includes a liberalisation of the rules governing which inherited diseases individual clinics can screen for.
More than one
The site will also allow patients to look at statistics on multiple births and urges patients to look for a clinic which has both a good success rate and a high number of single births.
Multiple births are risky for both mother and baby, but some prefer to transfer more than one embryo at once to increase the chances of a live birth and reduce the prospect of another round of expensive treatment.
At 32.3% overall success rates from IVF were highest for the under 35s, up slightly from the previous year, and indeed chances of having a baby increased between 2006 and 2007 for all age groups up to 42.
But they fell to just 3.4% for those aged 43-44, and 3.1% to those over 44.
The majority of clinics offer success rates within these figures, and while there are "some who come top and some who come bottom", patients should ask themselves whether it is really worth travelling many miles for marginal increases in success rates, the HFEA said.
"Every patient is different and most clinics have live births around the national average. These factors make it even more important for patients to see in detail what each clinic has to offer," says Professor Lisa Jardine, chair of the HFEA.
"Fertility treatment is big business in the UK. People can spend thousands of pounds in the hope of having a baby. It is only right that they have as much information as possible to help them make a choice about where they go for their treatment."
No price tags
Clare Lewis Jones, of the Infertility Network, also urged patients not just to consider success rates but to use the site to find a clinic which met "their own specific treatment needs".
A lack of transparency about cost is one of the key issues raised by patients, but the HFEA says it has no "statutory authority" to include this information on the site - and that in any event it would rapidly become out-of-date.
Private IVF treatment costs on average £3,500, but fees incurred by extra drugs and diagnostic tests can push this up to over £8,000.
It was also deemed inappropriate to provide information on where there had been mishaps, such as embryo mix-ups.
