VIENNA (Reuters) -- Doctors said Friday they had successfully separated conjoined twin girls just one day after their birth by Cesarean section in Vienna.

The twins, Michaela and Melanie, were born joined at the intestines -- a condition recorded only 20 times worldwide in the last 100 years.

Doctors at Vienna's General Hospital operated on the girls for seven hours Thursday without complications.

"The children have been separated, which was important for their survival," Dr. Ernst Horcher, who led the operation, told reporters. Both girls were in stable condition.

"They would not have been able to live for very long if they had stayed together," he said.