the story of addy + lily: birth + separation of conjoined twins

special editorial submitted by friends steward partner, children's hospital of philadelphia

When an ultrasound early in the second trimester showed they were expecting conjoined twins, Dom and Maggie began evaluating hospitals, willing to travel as far as necessary from their home in Chicago for care. After they met with the team at Children’s Hospital of Philadelphia, their decision was made.

On October 13, 2021, after nearly a year in intensive care at Children’s Hospital of Philadelphia (CHOP), 10-monthold conjoined twins Addison (Addy) and Lilianna (Lily) were separated by CHOP surgeons. What caused their connection is a mystery. What led to their successful separation is a medical marvel that would not have been possible were it not for expert prenatal diagnosis, seamless pregnancy management, successful delivery and the dedication of countless medical professionals.

Where the journey began In July of 2020, eager parents-to-be Dom and Maggie purchased their first home in the suburbs of Chicago in anticipation of expanding to a family of three. A month later, they learned not only that they were expecting twins, but that the girls were conjoined. It was a thoraco-omphalopagus connection, which means the girls were joined at the chest and abdomen.

An evaluation at Children’s Hospital of Philadelphia found that while Addy and Lily were joined at the chest wall, diaphragm and liver, they each had separate, healthy hearts.

Conjoined twins are very rare, occurring roughly once in every 50,000 births. Potential complications depend on where the twins are joined, which organs or other parts of the body they share, and the expertise and experience of the healthcare team. The maternal-fetal medicine (MFM) specialist in Chicago who made the initial diagnosis knew that in order for the twins to defy the odds and survive, they would need intensive care from a highly experienced team before, during and after birth.

Children's Hospital of Philadelphia (CHOP) is one of only a few hospitals in the country with experience delivering and separating conjoined twins. More than 28 pairs of conjoined twins have been separated at CHOP since 1957, the most of any hospital in the country.

The MFM called CHOP and spoke to Julie S. Moldenhauer, MD, Director of Obstetrical Services at the Richard D. Wood Jr. Center for Fetal Diagnosis and Treatment (CFDT). When the MFM explained what he saw on the ultrasound, Dr. Moldenhauer enlisted the help of the CFDT’s fetal therapy nurse coordinators to schedule the family for a comprehensive evaluation at CHOP.

At their first appointment, Maggie underwent extensive prenatal imaging to establish a clear picture of how the twins were connected to confirm that it was possible to separate them. The couple met with Dr. Moldenhaur and Attending Pediatric and Fetal Surgeon, Holly L. Hedrick, MD, who would separate the girls after birth, as well as a genetic counselor, radiologist, neonatologist, psychologist, and fetal therapy coordinator.

"They did a five-hour ultrasound, looking at every single fingernail and toenail," recalls Maggie, in awe of the care team's thoroughness. "They did everything they could to make sure they gave us the right answer of if a safe delivery and separation was possible.”

The evaluation found that while the girls were joined at the chest wall, diaphragm and liver, they each had separate, healthy hearts. And their shared liver vasculature and biliary drainage was favorable to divide between them. This meant they were excellent candidates for separation surgery.

“Children’s Hospital of Philadelphia gave us the confidence to say we can do this, and these little girls are going to be OK,” says Dom.

Co-managing the pregnancy

From that point until the family relocated to Philadelphia at 30 weeks’ gestation, Dr. Moldenhauer and the MFM in Chicago worked together to co-manage Maggie’s prenatal care. Conjoined twin pregnancies have an increased risk of serious complications. Conjoined twins have a high risk of prematurity and could be stillborn or die shortly after birth. Severe health issues — such as trouble breathing or heart problems — can occur immediately after birth.

During regular prenatal follow-up appointments, Dr. Moldenhauer and the MFM team at CHOP along with the obstetrical care team that includes obstetricians, midwives and nurse practitioners closely monitored the twins for any signs of complications. They performed biophysical profiles, an ultrasound method to ensure fetal well-being and that the twins weren’t in distress, measured the growth of the babies to ensure they were both gaining weight, and monitored amniotic fluid levels to ensure the twins weren’t developing polyhydramnios. The Center’s Psychosocial Services Team offered Maggie and Dom counseling and support services to help them cope with any mental and emotional challenges they faced during their care.

The goal was to get Maggie to 34 weeks’ gestation. As the due date approached, Maggie and Dom had frequent prenatal consultations with the High-Risk Obstetrical Team, as well as the Neonatal Surgery Team that would offer immediate delivery room management of the twins.

After nearly a year in intensive care, Addy and Lily were separated by CHOP surgeons and, a few weeks later, were discharged home to Chicago just in time for Christmas.

A high-risk delivery and separation surgery

Conjoined twins require surgical delivery by cesarean section (C-section) due to their anatomy. The High-Risk Obstetrical Team and Neonatal Surgery Team worked together to plan every detail of the delivery, from which type of uterine incision to make, to the safest way to position the twins during the delivery, to the logistics of attending to their medical needs immediately after birth. The team did a simulated walk-through of the delivery, rehearsing every detail.

Lily and Addy were born on Nov. 18, 2020, in CHOP’s Garbose Family Special Delivery Unit (SDU), the world’s first birthing facility within a freestanding children’s hospital designed just for pregnant women carrying babies with known birth defects. The MFM team was strategic in their approach to the uterine incision, delivering the girls through a low transverse incision rather than a vertical incision. This ensures that Maggie can attempt a trial of labor after cesarean (TOLAC) and deliver vaginally in the event of a subsequent pregnancy.

The twins spent four months in CHOP’s Harriet and Ronald Lassin Newborn/Infant Intensive Care Unit (N/IICU) where they received care for breathing and feeding issues resulting from their shared diaphragm and chest wall. They spent six months in the Pediatric Intensive Care Unit growing strong enough for their separation surgery.

Following the 10-hour separation surgery, the girls spent seven more weeks in CHOP’s PICU and did amazingly well. In true storybook fashion, they were discharged home to Chicago just in time for Christmas.

The family will never forget their journey at CHOP and the many overlapping teams that provided the highly specialized care their girls needed.

“I can’t thank the team at CHOP enough for their care, focus, experience and determination,” says Maggie. “We are just so in awe of what they've accomplished.”

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