Helping One Mom Make It Through a Mo-Di Pregnancy

Christina with husband Bryan and twins James and Weston

As an emergency room nurse, Christina Nix regularly encounters complex medical challenges. But nothing prepared her for being the expectant mother of Mo-Di twins.

Monochorionic diamniotic (Mo-Di) twins separate into two embryos 4 to 8 days after fertilization. The babies share a placenta, but each has their own amniotic sac (which surrounds the baby during pregnancy). Due to a shared blood supply, the twins are at greater risk for certain complications and tend to be born prematurely.

Christina and her husband Bryan, who had gone through in vitro fertilization, were thrilled to find out they would be having twins. When tests revealed the babies were Mo-Di twins, however, they began to worry.

"We went online and learned about all the bad things that can happen," Christina says. "My obstetrics office couldn't even handle this type of pregnancy because they didn't have appropriate monitoring, so friends of mine recommended I go to Brigham and Women's Hospital."

As it turned out, the Brigham was the perfect place for Christina and her family.

An Early Reason for Concern

Twelve weeks into the pregnancy, Christina had her first visit with Carolina Bibbo, MD, a maternal-fetal medicine specialist and director of the Brigham's Comprehensive Care Center for Multiples. Dr. Bibbo and the Center for Multiples team have extensive experience with pregnancies involving two or more babies, including those that are at higher risk of complications, such as Mo-Di twin pregnancies.

Right away, Dr. Bibbo saw reason for concern: An ultrasound showed signs of selective growth restriction. This is when monochorionic twins differ in size by more than 20 percent and one of the twins is growth-restricted.

"I was worried about the well-being of 'Baby A' and the possibility that he might pass away in utero, also putting his brother at risk since they shared the placenta and vascular connections," Dr. Bibbo says. "Cases of selective growth restriction that are diagnosed early in gestation are difficult to manage, as we don't know how they will evolve. It is very important that we follow these pregnancies closely."

Over the ensuing months, Dr. Bibbo kept a watchful eye on the babies' growth while also offering the Nixes a measure of reassurance.

"Dr. Bibbo is like a saint," Christina says. "From the first appointment there, she was very involved, talking with us every week and even taking time after hours to explain how we could move forward with things."

Christina started to relax a bit at 24 weeks — the earliest date the babies could be safely delivered, if necessary. At week 28, she was admitted to the Brigham for a projected 30 days of continuous monitoring. "Dr. Bibbo said she loses sleep over patients like me; she wanted me at the hospital so she could always know what was going on," Christina recalls.

Complications Necessitate a Delivery

Christina stayed on the Brigham's antenatal floor, which cares for women who have complicated pregnancies or require post-delivery hospitalization. Over the next few weeks, she underwent daily monitoring, which uncovered no warning signs. Dr. Bibbo stopped by often to say hello and review the ultrasounds.

At one visit during week 32, Dr. Bibbo detected new abnormalities on the ultrasound. Christina was taken to the labor and delivery floor. After several hours of monitoring, she developed preeclampsia, a condition characterized by high blood pressure (hypertension) that poses risks to both mother and babies. The time for the delivery had come.

Her subsequent cesarean section was relatively drama-free. Baby A (James), whose health had been such a concern throughout the pregnancy, needed a little assistance breathing but was in good shape overall. Although bigger than expected, he was still just 2 lbs., 12 oz. — small enough to fit in one of Bryan's hands. Brother Weston arrived three minutes later, weighing in just under 4 lbs.

The boys were soon transferred to the Brigham's Newborn Intensive Care Unit (NICU). Christina and Bryan visited for hours every day, helping to feed and bathe the boys and handle other parental duties. The couple found it stressful to see the boys hooked up to all sorts of monitors and, in James' case, a continuous positive airway pressure (CPAP) machine for 3 weeks to help him breathe. But they eventually became more comfortable in the NICU setting and developed a nice rapport with the nursing team.

Mom Christina with twins James and Weston

'They Made Me Feel So Much Better'

On Jan. 11, 2021 — 40 days after they were born — James and Weston got their doctors' okay to go home. In the weeks leading up to the discharge, Christina and Bryan received an education in everything that goes into caring for premature babies. They have since maintained the sleep and eating schedule established in the NICU, which has made home life more manageable.

As of early March 2021, Christina reports, James and Weston were doing well. Both were growing rapidly, sticking to their routines and starting to interact with their parents. Through the NICU Follow-up Program, Christina was taking the boys for physical therapy, speech therapy, nutrition services and follow-ups with one of the NICU doctors. And she was still hearing from two of the NICU nurses, who like to check in on the babies.

"I've told all of them, from Dr. Bibbo to the nurses on the floor, that they are my 'Brigham family,'" Christina says. "I was actually sad to leave the hospital because they were all so nice, comforting and reassuring. It was a difficult pregnancy, and they made me feel so much better."

Twins James and Weston

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