09/22/2025
Doctors successfully separate conjoined Chicago twins in 'superhero' procedure
The girls were born connected at the abdomen and chest, a condition known as thoraco-omphalopagus twins, meaning they shared a liver, diaphragm, chest and abdominal wall.
Addy and Lily were diagnosed prenatally, when parents Maggie and Dom went for their 20-week ultrasound appointment. At that time, Maggie and Dom assumed they were having one baby – until the ultrasound images showed two fetuses attached at the abdomen
After months of planning for a high-risk delivery via C-section, led by Julie S. Moldenhauer, MD, Addy and Lily were born on November 18, 2020, in the Garbose Family Special Delivery Unit (SDU), CHOP’s inpatient delivery unit.
Following a six-month stay in the pediatric intensive care unit, they spent four months in the newborn/infant intensive care unit (N/IICU) (PICU). CHOP plastic surgeon David W. Low, MD, inserted skin expanders to stretch the girls’ skin in preparation for separation surgery. Like small, collapsible balloons, the skin expanders gradually expand through injections, stretching the skin slowly over time so each girl would have enough skin to cover her exposed chest wall and abdomen after separation.
On October 13, 2021, after months of preparation, Addy and Lily underwent a 10-hour surgery and were officially separated at 2:38 p.m.
More than two dozen specialists, including general surgeons, anesthesiologists, radiologists, a cardiothoracic surgeon, and plastic surgeons, made up the surgical team under the direction of Holly Hedrick, MD. The surgical team repaired each girl’s chest and abdominal wall after the twins were separated.
Stephanie Fuller, MD, a cardiothoracic surgeon, ligated the girls’ patent ductus arteriosus and made sure both girls’ hearts were in the right position and functioning well. The stomach and chest walls of the twins were coated by two layers of mesh – one temporary and one permanent – before being covered with skin that had been stretched over several months.
“Our hope for the girls is that this is all behind them and that they go on to have full lives that are joyful,” says Dr. Hedrick.
On December 1, 2021, the Altobellis finally flew home to Chicago – one twin at a time, with one parent each – after living in Philadelphia for more than a year.
The medical staff that will look after the twins closer to home took care of them for two weeks at Lurie Children’s Hospital
“I can’t thank the team at CHOP enough for their care, focus, experience and determination,” says Maggie, tearfully. “We are just so in awe of what they’ve accomplished.”
