At last, Britain's donor-conceived children can know the truth about their origins | Zeynep Gurtin

A culture of secrecy around sperm and egg donations has given way to greater openness, helped along by a key legal change

Since 2009, the number of donor-conceived children born in the UK has more than tripled. They now account for one in 170 of all births, which means, as the Human Fertilisation and Embryology Authority (HFEA) chair, Julia Chain, puts it, a couple of donor-conceived children in every primary school, and an immeasurable amount of joy brought to families that could not have otherwise existed". While nearly half of all donor gametes are used by heterosexual couples suffering male- or female-factor infertility, much of the recent increase, particularly in the use of donor sperm, has been driven by women in same-sex relationships and solo mums.

The opening up of new routes to having children is a wonderful thing. But as the practice of donor conception - using donor sperm, eggs or embryos to create a family - has become more common, the resulting ethical dilemmas are also becoming more complex. Crucially, though, many warmly welcome the important changes happening this year, whereby donor-conceived children reaching 18 will finally have access to identifying information about their donors.

Zeynep Gurtin is a lecturer in women's health at UCL, an authority member of the Human Fertilisation and Embryology Authority and a fertility consultant

Some names have been changed