The center for Medically Assisted Procreation at San Raffaele Hospital in Milan, part of the Gruppo San Donato and operating under agreement with the regional health service, is at the center of two separate incidents involving errors and service disruptions. At the end of July 2026, a cryopreserved embryo intended for one couple was mistakenly implanted into another woman. A subsequent incident also emerged, dating back to last year, in which a freezer malfunction reportedly caused the loss of eggs belonging to twelve couples.

The embryo swap occurred when two women were in the center's waiting room. The patient who should have been called first was summoned second, leading to the implantation of the wrong embryo. Center staff noticed the error approximately eight minutes later. Twenty-four hours passed before the woman who had received the incorrect embryo was recalled and agreed to undergo endometrial aspiration to prevent a pregnancy with an embryo not biologically belonging to her couple. The second couple was not notified immediately and subsequently completed a successful transfer of a correct embryo.

ATS Milan suspended the hospital's Embryology Laboratory for fifteen days, citing non-conformities found during inspections, one of which was conducted jointly with the Ministry of Health. An internal report from San Raffaele itself described the incident as an expression of a comprehensive vulnerability of the system. The hospital expressed regret and reported having initiated internal investigation procedures and corrective measures, including reorganization of patient entry into the operating room and implementation of an electronic witnessing system for tracking biological samples.

The second case involves an incident that occurred last year: according to reports, the machine containing the eggs in the freezer malfunctioned, causing the loss of biological material from twelve couples. Details regarding the circumstances and any consequences for the patients involved have not been further specified.

According to scientific literature cited by sector experts, the probability of this type of error is approximately one case per ten thousand to twelve thousand assisted reproduction cycles, out of a total of about one hundred thousand cycles per year in Italy. A similar precedent was recorded in 2013 at the Pertini Hospital in Rome, when an error in assisted fertilization led to the birth of twins by a woman who had received embryos belonging to another couple, generating a complex legal dispute. Representatives of assisted fertilization center associations emphasized the importance of electronic sample tracking systems to prevent similar episodes.