Spindle transfer

9 July 2019

Spindle transfer in the treatment of infertility: an ESHRE position statement

ESHRE recommends extreme caution on the use of spindle transfer in human oocytes as a clinical application to address fertility problems. This treatment, also known as mitochondrial donation, involves the replacement of chromosomes of donor oocytes with the chromosomes of the patients, with the aim of correcting cytoplasmic disorders. This technique was originally developed for the treatment of women carrying life-threatening mitochondrial diseases to prevent the birth of affected children. After expert evaluation, it was made legal in 2015 in the UK, where each application, available only from licensed centres, is considered on a case by case basis and authorized only for those cases with a clear medical need and having no alternative.

Recently, researchers from a Greek Institute reported the birth of a healthy boy following the use of spindle transfer in a 32-year-old woman without an inherited mitochondrial disease, who had failed four previous cycles of IVF. Whether there was an identifiable ‘cytoplasmic disorder’ is unclear.

In the absence of solid evidence proving that spindle transfer or other forms of cytoplasmic donation provides higher live birth rates than conventional assisted reproductive technology, the application of spindle transfer as a remedy for fertility treatment remains vague and unproven. The recent report in Science on the untested interplay between mitochondria and nucleus remains unclear in the possible generation of short and long term side effects (Science 364, eaau6520, 2019). The current lack of solid scientific evidence providing safety reassurance requires more study and continued vigilance.

At the present stage, and until this technology has been proven to be effective and safe, ESHRE strongly discourages the use of mitochondrial donation to alleviate an infertility condition. In line with the document issued by HFEA, the UK fertility regulator, and co-signed by ESHRE and other scientific societies on new introduction in IVF, we support the need for a responsible use of evidence-based treatments in fertility practice (https://www.hfea.gov.uk/media/2792/treatment-add-ons-consensus-statement-final.pdf).