Part time working and job sharing in the NHS.

of referral to a specialist centre is important and should take account of the woman's age and the duration of subfertility. The longer the patient remains childless the lower the chance of conception, and as time runs out anxiety increases. Purchasing authorities are beginning to recognise the importance of subfertility and to purchase services for assisted conception. The techniques themselves are coming under increasing scrutiny from randomised trials. For example, 10 such studies have evaluated the effects of down regulation of the pituitary gland before ovulation was induced, and these have confirmed that this treatment is effective in doubling the rate of conception and halving the number of cancelled cycles.' General practitioners need information about the effectiveness of treatments for subfertility so that they can advise patients and contribute to any discussion about the level of funding of subfertility services. The newly published bulletin on the management of subfertility3 and the guidelines from the Royal College of Obstetricians and Gynaecologists on the topic4 will help such difficult choices. We thank Professor Allan Templeton of Aberdeen and Dr Patrick Vandekerckhove of Leeds for their helpful comments.