Conjoined twins are fighting for their lives after being born with their heads fused together at a hospital in Indonesia.

Putra and Siti Hadijah were delivered prematurely by emergency caesarean section today at a hospital in Banda Aceh.

Known as craniopagus twins, the condition occurs in about one in 2.5 million births. 

The hospital's best physicians are currently battling to keep them alive in Zainal Abidin Hospital's Neonatal Intensive Care Unit (NICU). It is understood their skulls are joined but it is so far unclear if they also share brain tissue, as well as vital arteries and nerves. 

Separating them can be dangerous, especially if there is significant blood flow between their brains. 

Around 200 pairs of conjoined twins are born alive every year but only half of the tragic youngsters survive past their first birthday.

Approximately 70 percent of all conjoined twins are girls. Female siblings are more likely to survive than their male counterparts as statistics show although more male twins conjoin in the womb, females are three times as likely as males to be born alive.