Controversial ‘3-Parent Baby’ Fertility Technique Fails to Deliver for Older Women

An experimental and much-hyped reproductive procedure that mixes DNA from three people is not effective at boosting the chances of having a baby for women ages 37 and older, according to doctors at a fertility clinic in Ukraine.

The technique, known as mitochondrial replacement therapy, involves taking a woman’s egg and shifting the majority of its DNA, known as the nucleus, into a hollowed-out donor egg. The shell of the donor egg contains healthy mitochondria, energy-making structures that have their own DNA. The resulting embryo ends up with DNA from the mother, father, and egg donor, so the technique is often referred to as “three-person IVF.” The procedure is controversial because many consider it a form of genetic manipulation.

Some fertility experts hoped that the younger mitochondria from the hollowed-out donor egg might rejuvenate the eggs of an infertile woman, thus increasing the chances of a successful pregnancy.

But new study results presented at a meeting of the American Society of Reproductive Medicine in Philadelphia show that might not be the case. The three-person IVF procedure was found to be...