On Monday, conjoined Tanzanian twins Ericana and Eluidi, both boys, will be separated in an 18-hour surgery at Apollo Hospital’s Vanagaram unit.

The pygopagus twins (conjoined at the end of the spine), born to a tribal couple from Kasumulu in Tanzania nine months ago, came to the Apollo Hospitals in June. According to doctors, one in two lakh deliveries could result in conjoined twins. While more than 60 per cent of them are stillborn, around 35 per cent die within a few days or months of birth. Pygopagus twins account for 17 per cent of conjoined twins.

Venkat Sripathi, senior consultant paediatric urologist, said only 30 sets of pygopagus twins had been reported so far and, of these, 26 were female. On Monday, the babies will undergo a series of procedures to be performed by a team of 20 doctors.

While the separation may take 12 hours, the rest of the procedures, such as providing each baby with a skin cover, would be done by plastic surgeons.