Studies raise safety and efficacy questions over MRT marketed as fertility treatment

Mitochondrial replacement therapy (MRT) — a technique originally developed to help women carrying serious mitochondrial disease mutations avoid passing those conditions to their children — is being marketed internationally as a treatment for age-related infertility, according to an investigation published by STAT News on 2 and 3 November 2026.

The investigation, conducted over several months, finds that women have travelled internationally to access MRT at clinics offering it outside the regulatory frameworks of their home countries. Researchers and ethicists quoted in the reporting describe the evidence base for using MRT to improve fertility outcomes in older women as thin, and suggest that some patients have not been adequately informed of the experimental nature of the procedure. STAT's coverage characterises the marketing as misleading.

MRT itself involves transferring the nuclear genetic material from an egg with damaged or disease-carrying mitochondria into a donor egg whose own nucleus has been removed, creating an embryo with nuclear DNA from two parents and mitochondrial DNA from a third — hence the colloquial label 'three-parent IVF'. Regulators in the United Kingdom have approved a tightly controlled pathway for MRT use in mitochondrial disease families; its use as a routine fertility intervention remains unapproved in most jurisdictions.

The reporting complements broader academic and ethical discussion about the pace at which reproductive technologies move from experimental settings into commercial fertility markets. No primary research paper is cited as the basis for these reports; the cluster draws on investigative journalism and expert commentary rather than a peer-reviewed publication.