Letter: NHS rationing

Sir: Like many practitioners in the field of in-vitro fertilisation, I am delighted that the Government is proposing to end the unfairness of the "post-code lottery" in the provision of fertility treatment on the NHS ("IVF age limit of 35 to be imposed", 23 August).

However, the proposed age limit for the female partner of 35 years seems biologically arbitrary and threatens further to distort the provision and uptake of IVF.

Success with IVF depends crucially on a woman's "ovarian reserve" (her ovaries' ability to respond to stimulation) and this is recognised to decline sharply from the late rather than the mid-thirties. For any individual woman in her thirties, her date of birth is unlikely to be more than a very approximate guide to her chance of success with IVF.

The imposition of the 35 years "cut-off" will inevitably encourage patients and practitioners to try IVF as a first-line treatment, before the woman becomes "too old" for free treatment, instead of trying one of the other less successful, but often far more cost-effective, alternatives such as ovulation induction or tubal surgery.

We live in an era in which the age of the first pregnancy is becoming much later than it was just a generation ago, because of changes in women's employment choices and social factors such as later marriage and remarriage. In view of this, it seems arbitrary to exclude from access to NHS treatment a significant cohort of women on the basis of their birth date alone.

In all other fields where attempts have been made to "ration" health- care on the grounds of age (such as a "cut-off" of 65 for renal dialysis), this "ageist" policy has subsequently become discredited, and been abandoned.

Dr GILL LOCKWOOD

John Radcliffe Hospital

University of Oxford