Selective Intrauterine Growth Restriction: Hattie and Nora’s Story

Brittany was 19 weeks pregnant with monochorionic twins — meaning they shared a single placenta — when an ultrasound revealed that one was growing more slowly than the other. The maternal-fetal specialist at their hospital in New York City sat down with Brittany and her husband, Ben.

“She said, ‘You need to get to Children’s Hospital of Philadelphia (CHOP). Call them today. You may have to see them tomorrow,’” Brittany remembers. The specialist warned the couple that it was possible they may lose one or both twins.

The diagnosis

Brittany called CHOP and was scheduled for a comprehensive evaluation at the Hospital’s Richard D. Wood Jr. Center for Fetal Diagnosis & Treatment (CFDT) first thing the next morning. The couple borrowed a friend’s car and made the two-hour drive from their home in Manhattan to Philadelphia.

Brittany remembers arriving early that morning feeling anxious and disoriented. The staff greeted her and Ben with a printed itinerary of the day’s tests and consultations. They would be meeting with a genetic counselor, nurse coordinator, maternal-fetal medicine specialist, and fetal imaging experts, among others. Brittany would have a high-resolution fetal ultrasound and fetal echocardiogram. There was even time blocked out for the couple to eat lunch.

“For someone dealing with such unknown circumstances, it was exactly what I needed,” says Brittany. “It was incredibly helpful as a first-time mom in a horrible situation.”

By that afternoon, they had a diagnosis: selective intrauterine growth restriction. Also known as sIUGR, the condition occurs when monochorionic twins share the placenta unequally. One fetus receives less blood flow and nutrition, causing its growth to slow.

The condition is rare, occurring in roughly 10 percent of monochorionic twin pregnancies. sIUGR puts both twins at risk because their circulatory systems are connected by blood vessels through the placenta. If the smaller fetus dies in utero, the other’s blood pressure may drop, possibly causing neurological damage or death.

Keeping a close eye on the twins

The team at the CFDT recommended that Brittany return for weekly monitoring. If the smaller fetus stopped growing or developed signs of abnormal blood flow through the umbilical cord to the placenta, a procedure called a selective cord occlusion could be used to stop blood flow to the growth-restricted twin and protect the healthier twin’s life.

“It was incredibly overwhelming,” she recalls. “My biggest fear was, how do you choose to save one baby and not the other. How do you make that choice as a mom?”

The CFDT offers a variety of counseling and support services to help families cope with the emotional impact of a baby’s diagnosis. These services include a psychologist, psychiatrist, chaplain, and dedicated child life specialist as well as social workers.

For the next few weeks, Brittany and Ben traveled back and forth to CHOP where the fetal team monitored the pregnancy closely. Weekly ultrasounds kept a close eye on the growth of both twins to make sure their sIUGR didn’t progress to a more severe type.

Unlocking the mysteries of sIUGR

Because sIUGR is a relatively new diagnosis, not much has been published yet about the condition. However, the couple found comfort in knowing they had an expert team watching over their twins.

Since 1995, more than 3,000 complicated multiple gestation pregnancies have been referred to the CFDT. Seeing such a high volume of monochorionic twin pregnancies gives the team an unparalleled level of experience in diagnosing and treating sIUGR and similar conditions.

The CFDT team is using that experience in ongoing research to better understand the problems that can occur as a result of monochorionic pregnancies, and improve outcomes. They gave Brittany and Ben copies of recent research to help them learn all they could about the condition. The couple devoured the information.

The twins make their appearance

When the twins made it to 24 weeks without any additional complications, Brittany’s local maternal-fetal medicine specialist took over the weekly monitoring. Preterm deliveries are common in pregnancies affected by sIUGR, so it’s important to consult with a specialized delivery center that is equipped to offer expert neonatal care.

At 31 weeks, Brittany was diagnosed with preeclampsia and admitted to her local hospital. Less than two weeks later, the smaller twin’s heart rate dropped, putting both babies’ lives at risk. The decision was made to deliver the babies by c-section.

“All I could focus on was hearing them cry,” says Brittany. “I felt that as long as I could hear that, everything would be OK. And suddenly there were two incredibly loud, beautiful cries. I remember looking at my husband, laughing in awe, and saying ‘Welcome to the rest of our lives!’”

Hattie, the growth-restricted twin, weighed 2 lbs. 8 oz. Nora was 3 lbs. 3 oz. Brittany and Ben saw their girls briefly before they were admitted to the neonatal intensive care unit (NICU). After 3 1/2 weeks, Nora was healthy enough to go home; Hattie stayed in the NICU another week and a half.

Now, more than two years later, the twins are active, loving toddlers with unique personalities.

“There’s not a day that goes by that I don’t think about how very different our outcome could have been, and how grateful I am to have two happy, healthy, determined little girls,” Brittany says.

Today, Brittany volunteers at the NICU where her girls began their lives and serves on the family advisory council. Remembering how alone she and Ben felt with their diagnosis, she hopes that by sharing their story she can bring comfort and hope to others going through similar experiences.

Published June 2017