Vienna, Austria -- A baby who underwent heart surgery while still in the womb was pronounced fit on Wednesday, a week after her birth. The six-hour surgery in October in Linz, Austria, about 80 miles west of Vienna, involved the reopening of a valve in the right ventricle of the unborn child's heart. It was performed by specialists Wolfgang Arzt and Gerald Tulzer.

Doctors said the operation was the first of its kind for the region.

Baby Johanna was then born by Caesarean section on Jan. 3, the Austria Press Agency reported. She weighed 5.7 pounds. The agency did not give her last name.

Both doctors said Wednesday after medical tests that Johanna's condition was good despite having undergone a further operation after her birth.

Left untreated, she would not have survived until birth, they said.