A Spanish couple has won a lawsuit in a Belgian court because an IVF clinic produced twins with the wrong genetic make-up. The parents were awarded €38,000 for “shock” and “impoverishment”.

It was the first time that a Belgian court had found that a healthy child can be the cause of loss to parents.

A previous child born to the parents had beta thalassaemia, a genetic disorder which can be corrected with a bone marrow transplant. They wanted another child who could supply healthy bone marrow – a so-called “saviour sibling”.

Doctors at the Universitair Ziekenhuis in Brussels promised to do IVF and “pre-implantation genetic diagnosis” to ensure that the second child was a suitable donor. To the parents’ dismay, however, the clinic selected an embryo which proved not to be a match. Worse still, the embryo twinned.

The parents repeated the procedure at a hospital in Madrid and the fourth child proved to be a match.

Then the parents successfully sued the Belgian hospital. The judge ruled that the Spanish couple had “wanted two or three children within their family project, but under no circumstances four”.