Question to the Department of Health and Social Care:

To ask Her Majesty's Government what assessment they have made of the statement on the Human Fertilisation and Embryology Authority website about the “limited evidence on risks and success rates” for mitochondrial replacement techniques; how many embryos have been generated to date using each particular technique; how many such embryos have been transferred to patients; how many confirmed pregnancies have resulted since then; and how such outcomes remain consistent with expectations from the scientific review by the HFEA in 2016 about the safety and efficacy of methods to avoid mitochondrial disease through assisted conception.

The Department has not made an assessment. The statement aims to provide basic information to potential patients and the reference to limited evidence on risks and success rates reflects that this treatment has only been available in the United Kingdom for the last few years.

The Human Fertilisation and Embryology Authority has advised that to date it has licensed 24 patients as eligible for mitochondrial donation treatment in the UK. To protect patient confidentiality, information on the number of embryos produced, transferred, and confirmed pregnancies cannot be disclosed. No assessment of the safety and efficacy of mitochondrial donation treatment has been made to date as the number of treatments in the UK is low.