In the science fiction movie Gattaca, the hero, Vincent, is an “In-Valid” – someone whose only crime is to be conceived in a moment of passion rather than in a Petri dish. His brother, by contrast, is a Valid, created by a process designed to ensure the optimum recombination of his parents’ genes. In-Valids are condemned to a life of menial jobs and discrimination. To realise his dream of becoming an astronaut, Vincent has to buy a Valid’s identity.

It’s a scenario that is difficult to imagine from today’s viewpoint. Yet could we be moving towards an age in which entering nature’s genetic lottery is no longer seen as a desirable way to bring a child into the world? Might natural conception even come to be thought of as irresponsible, as bad as smoking while pregnant?

Reproducing the traditional way is undoubtedly flawed. Worldwide around 1 child in 16 is born with a mental or physical disability due to a genetic defect, and most of us probably carry gene variants that predispose us to serious illnesses later in life. How much safer it would be to go along to the fertility clinic, have some embryos created and pick the one or two that will produce the healthiest baby.

IVF has become commonplace, and top clinics boast pregnancy rates of more than 30 per cent for each cycle – better than the 1 in 4 chance of conceiving the natural way and likely to improve further. Until recently, though, IVF was only for those with fertility problems. The rapid development of pre-implantation genetic diagnosis is starting to change this. Increasing numbers of …