An embryo mixup has led to a woman in Rome being impregnated with the twins of complete strangers.
Italy's Health Ministry has launched an investigation into how a woman undergoing fertility treatment was given the embryos of another couple and how the mistake was only discovered when the woman was three months' pregnant.
The mistake happened on December 4, when four different couples were receiving treatment at a specialist fertility unit at the Sandro Pertini Hospital in Rome, Italy's La Stampa newspaper reported on Sunday.
It was not yet known if any of the other women were also implanted with incorrect embryos.
Italian Health Minister Beatrice Lorenzin, who only learnt of the mistake through press reports, said the investigation would look at whether the hospital had "respected all the legal procedures".
"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," she said.
Rome's local health authority halted all embryo implantations at the clinic when a "genetic incompatibility was discovered between the parents and the embryos on March 27.