League tables of in vitro fertilisation clinics misinform patients

Editor—Marshall and Spiegelhalter have done a valuable service in questioning the reliability of the Human Fertilisation and Embryology Authority’s league tables of in vitro fertilisation clinics.¹ Unfortunately, the tables are probably even less reliable than these authors suggest.

The authority reports adjusted life birth rates, which are based mostly on the female patient’s age. As the method of adjustment is unpublished one cannot judge whether the various factors are weighted correctly. Moreover, this adjustment does not embody all factors affecting outcome. These include an accurate record of the number of previous cycles of in vitro fertilisation, basal follicle stimulating hormone concentrations, amount of gonadotrophin needed before eggs are collected, total ovarian response, and number of embryos transferred. Some clinics attempt to reduce the incidence of triplet pregnancy by transferring only two embryos except where prognosis is known to be poor. Others try to increase success, but also increase risks, by routinely transferring three embryos.

Commercial interests are involved in practising in vitro fertilisation. Most patients are forced into the competitive private sector because of inadequate NHS funding. There is commercial pressure on NHS clinics too, because they are less viable if purchasers believe that they have poorer success rates than others. Many clinics therefore unreasonably exclude women whose prognosis is regarded as unfavourable. This may improve league results, but is detrimental to women whose only chance of a baby is to have in vitro fertilisation. Pressure to be high in the league table also inhibits research—for example, clinics are increasingly reluctant to undertake controlled trials investigating potential improvements because these may affect their results adversely.

Evidence also suggests that the existence of league tables discourages some clinics from reporting their results fully to the Human Fertilisation and Embryology Authority. Some may abandon individual in vitro fertilisation cycles early when a poor response is anticipated and convert the patient to gamete intrafallopian transfer, which is unregulated. Competition to succeed at all costs also accounts for too many patients receiving three embryos. This has led to unacceptable rates of triplet pregnancy, with its high cost to the patient and NHS alike.

The Human Fertilisation an Embryology Authority repeatedly claims that it is “not producing leagues tables” (Ruth Deech, Human Fertilisation and Embryology Authority press release, 2 Dec 1997). The tables are certainly perceived as such. The authority has a statutory duty to maintain adequate public information The current tables misinform and damage the interests of patients in different ways. Re-evaluation of this important issue is needed.