An upcoming article in the journal Fertility and Sterility shows that some disabled parents in the US are using pre-implantation genetic diagnosis (PGD) to create children like themselves. The two disabilities mentioned are deafness and dwarfism. A survey of 190 American IVF clinics recently found that 3% had deliberately used PGD at some stage "to select an embryo for the presence of a disability".

Most IVF clinics turn down such requests, but two leading IVF specialists were quoted in the New York Times as saying that they would refer families to more obliging doctors. The Times interviewed Mary Ellen Little, a dwarf who has two daughters with dwarfism. The second was deliberately selected. Some disabled parents feel that having children who share their problems will strengthen family ties.

"The small number of PGD centers selecting for mutations doesn't bother me greatly," writes Dr Darshak M. Sanghavi in an op-ed article. "After all, even natural reproduction is an error-prone process, since almost 1 per cent of all pregnancies are complicated by birth defects -- often by more disabling conditions than dwarfism or deafness."