A pregnant Italian got the shock of her life on 27 March after she found out the twins she’s carrying might not be hers. By then she was already three months pregnant.

Reports of the shocking discovery pointed to a possible blunder at the time the woman was treated at the fertility unit of the SandroPertiniHospital in Rome. On 4 December, the woman was among the four different couples who received treatment at the clinic.

It is not yet known if the other women are also carrying the wrong baby.

The Health Ministry has launched an investigation of the mix-up and has ordered the hospital to stop all embryo implantations until further notice.

Minister Beatrice Lorenzin on Sunday said if it weren’t for the press, they would not have known there was such a problem. She said those in charge of the investigation will check if the hospital ‘respected all the legal procedures.’

She added that ‘The national standards on assisted fertilisation, which are based on European directives, are very rigorous, and if applied correctly, guarantee the traceability of all biological material used in the reproduction process.’

Geneticist Giuseppe Novelli will head the investigation which will also see if the other women were affected by the mix-up.