Some couples trying unsuccessfully for a baby are as likely to conceive using insemination than expensive IVF treatment, a study says.

The research, published in The Lancet, looked at both subfertile men, and couples for whom the reasons for not conceiving were unclear.

Although many are offered intrauterine insemination (IUI), in which sperm is injected into the uterus when the woman is ovulating, some are given IVF, in which sperm and eggs are combined outside the body and fertilised embryos re-implanted.

IVF is far more expensive, and requires more highly trained staff, as well as being more uncomfortable for the woman.

A third of the couples were given IVF by the dutch researchers, a third IUI and a third IUI in addition to low-dose fertility drugs.

The project found no significant differences in the number of live births between the three methods, meaning IUI, as the cheapest option, is the most cost-effective.

The only factor which reduced the chance of success was the increasing age of the woman.

Not available

Fertility treatment is not available to many couples on the NHS, as health authorities may choose to restrict it on the grounds of cost.

Dr Marion Hall, from the Department of Obstetrics and Gynaecology at the University of Aberdeen, said: "IVF is an expensive procedure that is inconvenient and uncomfortable for the woman and requires highly trained staff.

"Although IVF is more effective on a per-cycle basis, IUI in spontaneous cycles is a safer and cheaper option with a similar culmulative pregnancy rate.

"Funding bodies should ensure that IUI is routinely offered first to couples with unexplained or male-factor subfertility."

IVF, however, may still be the first treatment for many other common fertility problems