Doctors caring for quadruplets born prematurely to a 65-year-old Berlin woman say the babies are still in intensive care, but have been gaining a little weight and are being given their mother's milk through feeding tubes.

Mother Annegret Raunigk left intensive care 48 hours after the delivery and is doing well. She gave birth by cesarean section to a girl and three boys during her 26th week of pregnancy at Berlin's Charite Hospital on May 19.

The director of obstetrics at Charite, Wolfgang Henrich, said Wednesday Raunigk is believed to be the oldest mother to have ever delivered quadruplets.

Raunigk already has 13 children aged 44 to 9 from five other fathers. She traveled abroad to have donated, fertilized eggs transferred — a procedure that is illegal in Germany.