People conceived with the help of donated eggs or sperm will be able to contact their genetic parents if they are happy to be identified.

A voluntary register of adults conceived through donations was launched yesterday by Melanie Johnson, the public health minister.

The government has ruled that children born after next year will, when 18, have the right to know donors - a move some fertility doctors fear might reduce donations.

The register will only help up to 12,000 of the 37,000 so far born after treatment, those born before the Human Fertility and Embryology Authority started regulating the field in 1991.

If a success, the scheme is likely to be extended to those born between 1991 and 2005.

Those over 18 and their genetic parents can register with UK DonorLink (ukdonorlink.org.uk) and be DNA tested.