The monitor beeped at a constant pace, sounding out her heartbeat. Morgan B. recited the names of her family members and loved ones to herself, uncertain whether she would wake up to see them again. In an operating room at Rhode Island Hospital, Morgan awaited surgery on the two fetuses in her uterus.

“The odds were completely against us,” Morgan says, remembering that day. “I was putting the lives of my future children, and my own, in the hands of complete strangers.” It was the most frightened she’d ever been, she says.

Three days earlier, on a Friday the 13th in November 2020—19 weeks into her pregnancy—Morgan’s regular check-up had led to the most difficult conversation of her life. It was early in the COVID pandemic, and she was alone in Hasbro Children’s Hospital at her ob/gyn appointment. The ultrasound of Morgan’s twin fetuses had showed an anomaly: One of the twins (Baby A) had cardiac failure and the other (Baby B) had too much blood in its body.

Morgan’s doctor’s suspected twin to twin transfusion syndrome (TTTS). In an ideal monochorionic (identical) twin pregnancy, each twin uses about half of the placenta and blood flow. While blood circulates from each fetus to its part of the placenta, some blood flows back and forth between the two fetuses. However, in 10 percent to 15 percent of cases, an imbalance arises in blood flow and placental share between the twins. One twin gives too much blood (the donor) to the other twin (the recipient). This is TTTS, and it is dangerous for both twins.

“The donor can experience growth restriction for two reasons,” says TTTS expert François Luks, MD, chief pediatric surgeon at Hasbro Children’s and the J. Murray Beardsley Professor of Surgery at The Warren Alpert Medical School of Brown University. The donor twin “is spending way too much energy providing blood to the recipient,” he says, and “its placental share may be too small.”

In severe TTTS, Luks adds, the donor twin may develop anemia and high-output heart failure due to chronic blood loss. “It’s transfusing blood to its twin. It’s the same thing as if you were slowly bleeding out,” he says.

After the first trimester, amniotic fluid—contained in separate amniotic sacs for each twin—is composed mostly of fetal urine. When blood volume decreases in TTTS, the donor fetus’s body will work to conserve fluid by decreasing urine production. As a result, the donor’s bladder fills poorly, and amniotic fluid volume decreases, leading to a condition called oligohydramnios (low amniotic fluid) or anhydramnios (no amniotic fluid). The surrounding amniotic membrane tightly wraps around the fetus, making what is called a “stuck twin.”

“In contrast, if the recipient gets too much blood, it’s pretty much the same as drinking gallons of water every day. What’s going to happen? You’re going to make more urine,” Luks says. The recipient twin receives excess blood, leading to increased urine production and polyhydramnios (excess amniotic fluid). This combination of low fluid around the donor and excessive fluid around the recipient, known as the poly-oli sequence, defines the TTTS diagnosis.

“We need to intervene quickly,” Morgan remembers the doctor saying. But it was a weekend, when expert surgeons were often unavailable and operating room schedules were limited, with rooms reserved for dire emergency trauma cases. The hospital sent Morgan back to her home in Massachusetts with instructions to return on Monday.

“Do not Google TTTS and go down the rabbit hole,” the nurse coordinator of the Fetal Treatment Program told her. TTTS can occur in any twin pregnancy in which the twins share the placenta and when the blood vessels of the placenta develop abnormally. TTTS typically produces no symptoms in the mother.

Still, Morgan says she couldn’t help but feel guilty. “It was like walking around with a ticking time bomb,” she says. It was her first pregnancy, and there was nothing Morgan and her husband, Mike, could do that weekend other than try to understand what had happened.

A Fighting Chance

The progression of TTTS is staged, based on doppler ultrasound findings. In Stage I, ultrasound shows a significant imbalance in amniotic fluid volume between the twins. In Stage II, the bladder in the donor twin becomes invisible, due to low urine production. In Stage III, umbilical vessels show abnormal signals. In Stage IV, hydrops fetalis (fluid accumulation) and heart failure develop in either twin.

TTTS does not necessarily progress linearly through stages, however. The condition may fluctuate between stages, improve spontaneously, or rapidly worsen. Therefore, deciding the timing and type of intervention is challenging for clinicians. Ultrasound also has limitations. A fetus cannot be physically examined, and clinicians need to infer the health of the fetuses based only on imaging findings.

“It’s frustrating, because you wish you could predict better,” Luks says. “Ultrasound is fantastic, but it’s not perfect. We think we understand what’s going on, but we still don’t.”

One of Morgan’s twins was in Stage Ⅲ cardiac failure with an invisible bladder. The other showed signs of fluid under its skin. Early interventions carry risks to both mother and babies, but delaying interventions risks disease progression and danger to the fetuses. Morgan and her husband faced a dilemma.

On Monday, Nov. 16, 2020, Stephen Carr, MD, their maternal-fetal medicine physician, gave Morgan and Mike three options: do nothing, which would leave little chance for the fetuses to survive; terminate the pregnancy; or undergo an ablation surgery. In this procedure, a surgeon would use a laser to close the placental blood vessels that were causing the imbalance. Brown’s Fetal Treatment Program generally uses a conservative management approach, reserving the surgery for Stage II or higher. While this strategy risks intervening later, with more advanced disease, it minimizes unnecessary procedures and avoids exposing mothers and fetuses to potentially unnecessary risks.

Morgan learned that the surgery had a 60 to 70 percent success rate—that is, of both fetuses surviving. There was also a chance that only one of the twins would make it, and Morgan would have to carry the fetus in her womb for the remainder of the pregnancy. As happens in 10 to 15 percent of surgeries, both twins could perish, or Morgan could go into labor before the babies could survive outside the womb. “[The odds are] bittersweet,” Luks says. The doctors gave Morgan and Mike the night to decide.

Despite the risks, they decided to undergo the surgery. “We wanted to give the girls a chance,” Morgan says.

The next morning, a Tuesday, Morgan and Mike drove to the hospital. They called family and friends along the way. Morgan remembers everything happening so fast that she and Mike had no time to tell everyone, nor to process their situation themselves. At the hospital, Mike was not allowed in the preoperative room because of COVID protocols, and Morgan was again left alone in a room full of strangers. Morgan saw the nurse who’d cared for her the week before, carrying a cooler with blood in case Morgan suffered from excessive bleeding during surgery. In that instant, Morgan realized that if she bled out, not only her twins would die, but she would, too. “I had only lived 27 years. I wanted to save my life,” she says.

Luks strode into the operating room. In case of an emergency, he told Morgan, they would have to perform a hysterectomy, which would leave Morgan unable to conceive biologically forever. He reassured Morgan that in the years that they had performed TTTS surgery, they had never had to do a hysterectomy. There had been one case in which they had to perform an emergency C-section, when one of the babies had become bradycardic. “No one would feel at ease hearing that,” Morgan says, “but I really appreciated that he was being completely honest.” She decided to put her life and reproductive capacity in Luks’ hands and signed the surgical consent.

“How do you know when we are no longer at risk?” Morgan asked the nurse. “When the girls are born,” the nurse said. The thought that anything could happen even after a successful surgery was daunting. Morgan imagined the faces of family and friends as the anesthesia took hold.

Almost a Miracle

Luks made a small incision on Morgan’s abdominal wall. After locating the surface of the uterus, he put a fine needle through the uterus membranes and into the amniotic cavity of the recipient fetus. He removed the needle and ran a 3-millimeter-diameter tube inside the cavity. Into the tube the surgical team ran a telescope with a camera. This allowed them to examine the placenta and identify where the blood vessels of one twin met the blood vessel of the other. In an ideal TTTS scenario, the connected blood vessels form a line in the middle of the placenta, which the team can use to find the connected vessels. Using a fine laser fiber less than half a millimeter diameter, Luks blocked every blood vessel connecting the two twins.

“There should be a no-man’s-land, where there are no vessels at all. Any vessel that crosses this imaginary line, we use a laser to close it,” Luks says.  

Morgan woke up three hours later, drowsy and panicky. “What’s going on? Are the girls OK? Did they take my uterus?” she asked. She was relieved to see the same nurse’s familiar face. Everything is fine, the nurse said. She told Morgan that she had watched the whole surgery and that the doctors had done very well.

The challenge didn’t end there, however. Morgan was required to come in for ultrasounds and other monitoring twice a week, driving from Massachusetts to Providence each time. The remaining pregnancy was also physically painful, as the twins were kicking on her internal incision.

  On Dec. 24, in her 25th week of gestation, the nurses detected contractions of the uterus and a drop in one of the twins’ heart rates. Morgan was admitted to the hospital so she could be monitored 24/7. For the next four-and-a-half weeks, she was isolated in the hospital, with no one allowed to visit. She felt like a prisoner, she says, now being monitored three to six times a day, uncertain of what would happen. Every week, the doctors explained to her the rate of survival or risk of brain hemorrhage in the twins if she were to go into labor that week. “I was so lost, so hopeless, having no control over the situation,” Morgan says.

In January, Morgan had made it to 32 weeks. Doctors told her this was “almost a miracle,” Morgan says. However, the twins were showing signs of TTTS again. Carr said it was time for a C-section. The girls have done their part, he said, let us work hard and let them rest.

“That meant a lot,” Morgan says, tearing up as she remembers. “We had been through a lot, but ultimately, the girls were the ones fighting.”

On Feb. 10, 2021, staff wheeled Morgan once again into surgery. Soon a surgeon pulled the twins out of Morgan’s body. Baby A came first, 3 pounds 14 ounces and very red, and not needing oxygen assistance. Baby B emerged next, 2 pounds 14 ounces, and needed a continuous positive airway pressure (CPAP) machine for six hours. Thirty nurses, doctors, and other practitioners had gathered in the room; they all smiled with relief. Finally, two babies had arrived in the world, crying and healthy. All they needed was to grow.

“Good news was unfamiliar,” Morgan says, crying.

The Long View

The Fetal Treatment Program of New England celebrated its 25th anniversary last year. Luks reflects on the TTTS surgeries he has performed. “There are some dark moments. You feel almost helpless; it’s a stab in the dark, and you’re not sure that it’s gonna work,” he says. “And then, you get a card from families.”

From the drawer in his office, he pulls out a stack of Christmas cards, many with pictures of twins smiling, healthy, and grown. “You can’t help everybody all the time, but knowing that you’ve helped some people is a pretty incredible feeling,” Luks says.

The veteran surgeon cherishes the long-term connection he has formed with many of his patients and families. He’s proud that he has patients who are now 25 years old, whom he has “known” for 26 years: “I’ve known them even before they were born,” he says, smiling.

One recent day, recalling their brush with TTTS, Morgan and Mike look out the window of their home. The twins, age 4, play in the backyard. Sometimes the parents wonder why they had to endure so much for everything to turn out OK in the end. They can still go back in time to when they had prepared for worst-case scenarios. There are specific moments, fears, and conversations they still hold on to. And yet, the twins are thriving—and are starting preschool.

“Now more than ever, it’s important to look back and realize,” Morgan and Mike say, that “family, doctors, nurses, the region we live in, all came together and made this possible, and we are extremely grateful.”