A ground-breaking surgery successfully separated eight-day old identical twins - the world's youngest pair of conjoined twins to be surgically disjointed. On Dec. 2, 2015, identical twins Maya and Lydia were born two months premature, along with their triplet sister Kamilla. Lydia and Maya were born conjoined at the chest and liver.

The five-hour operation was conducted by a team of five surgeons, six anesthesiologists and two nurses at the Bern University Hospital in Switzerland where the triplets were born. Despite being two months premature, Lydia and Maya's condition is stable. The doctors initially planned for the twins to settle post-birth and conduct the surgery after a few months.

However, one of the twins suffered hypertension after a week. The other twin suffered hypotension, which is the reverse condition. The twins weighted only 2.4 pounds each and the conditions were severely dangerous to both. The doctors then decided to separate the twins ahead of schedule, which would make them the youngest pair to undergo such operation.

Geneva University Hospital's Barbara Wildhaber led the operating team who conducted the surgery on Dec. 10, 2015. Separating the livers will create massive pressure to the twins, said Barbara who heads the hospital's pediatric surgery unit. Wildhaber said the team was prepared for a scenario wherein they cannot save both babies but the ground-breaking surgery proved successful. Wildhaber added that she will remember the twin's surgery her entire career.

"It is the first successful operation of such small conjoined twins in Switzerland and possibly even worldwide, and therefore - apart from great luck for the parents - a medical sensation," said [pdf] Bern University Hospital.

The surgery was organized by Bern University Hospital's Department of Paediatric Surgery who worked with a team of pediatric surgeons from the Hôpitaux Universitaires de Genève (HUG).

While Kamilla is also doing well, Lydia and Maya started putting on some weight as well as breast feeding after the surgery.

Also known as "Siamese Twins," conjoined twins are born once every 200,000 live births. About 40 to 60 percent of Siamese twins are delivered stillborn while 35 percent live for just one day. The total survival rate is between five to 25 percent. Conjoined twins develop from one fertilized egg and share one placenta and amniotic cavity.