A baby was born in Mexico with "three parents," about five months ago to parents who had had four miscarriages and lost two children, the New Scientist reported.

Jordanian parents gave birth to in Mexico through an IVF technique which used one donor egg along with the mother's egg to process the fertilization. The doctors waited for five months to announce the news as they wanted to be certain about the health of the baby.

The mother's DNA is a carrier of Leigh syndrome which affects the nervous system of the infants because of which her children died at young age.

Leigh syndrome in the DNA was traced to her mitochondria, which is present in all the cells of body outside the nucleus, including in the egg. So, the cellular components of mother's egg were removed and a donor egg's cell was used to place the nucleus.

Dr. John Zhang from New York City's New Hope Fertility Center headed the critical procedure which involved delicately removing nucleus from the mother's eggs and inserting it into a donor egg after discarding its nucleus. The egg was then fertilized with the sperm of the father. The embryo was then implanted in the mother. The baby was born after a full term of nine months.

The method has not been approved in the US, so the doctor and his team went to Mexico perform the genetic engineering, where Zhang says "there are no rules."

The mother herself has no symptom of Leigh syndrome, but her daughter died at the age of six and her second child died at the age of eight months from the disease.

Dr. Zhang says that he did the right thing because "to save lives is the ethical thing to do."

Experts from UK, where this IVF technique is legal, said that the doctors carried out the procedure ethically.

Sian Harding, Professor of Cardiac Pharmacology at the National Heart and Lung Institute, Imperial College, London, said that the team's work was ethical because it did not destroy any embryos, and chose fertilization of a male baby so that the inherited donor mitochondria will not be passed on to the next generation.

"It's as good as or better than what we'll do in the UK," she said.

However, other physicians remain skeptical.

"Even if these babies are born they will have to be monitored all their lives, and their children will have to be as well. We do not yet know the interaction between the mitochondria and nuclear DNA. To say that it is the same as changing a battery is facile. It's an extremely complex thing." said Dr Trevor Stammers, Program Director in Bioethics and Medical Law at St. Mary's University.