On Roberts’ medical record, his obstetrician wrote: singleton.
“I remember walking away from the very first scan so happy,” said Roberts, 39, who lives in Wiltshire, England.
But his excitement suddenly turned to shock five weeks later at the 12-week ultrasound appointment, when the sonographer spotted something astonishing: It seemed like Roberts was suddenly carrying two babies – one of which was considerably less developed than the other. The room fell silent.
“I thought something terrible had happened,” said Roberts. “The sonographer looked at me and said, ‘Do you know you’re having twins?’ “
But it wasn’t a typical set of twins, Roberts learned. Her pregnancy was diagnosed as superficial, a rare condition in which an already pregnant woman conceives another baby.
Roberts’ pregnancy is one of the very few cases of superficiality recorded in the medical literature, said her obstetrician, David Walker.
Superficiality is so rare, in fact, that Walker struggled to diagnose it at first. In his 25 years as an obstetrician, this was something he had never seen before.
“It just doesn’t happen,” Walker said, adding that it took several tests before he could confidently diagnose the disease.
“We were worried because the second twin was much smaller. It was only by scanning regularly and seeing that the growth rate was consistently three weeks behind that we realized these were superfetations, ”he explained.
The actual number of superficial cases is not known, but according to a 2008 report in the European Journal of Obstetrics & Gynecology and Reproductive Biology, less than 10 cases of the phenomenon worldwide were recorded at the time.
Usually, hormonal and physical changes during pregnancy prevent another conception from occurring. This was not the case for Roberts.
“Instead of stopping ovulation, she released another egg about three or four weeks after the first one, and the egg was miraculously successful in fertilizing and implanting in her uterus,” Walker said.
Although Roberts takes a fertility drug to stimulate ovulation, Walker said he “isn’t convinced” that the drug – which can increase the chances of having multiples – is what caused the superficiality.
“She didn’t release two eggs at the same time, which the drug normally does,” Walker said. “But we have no way of proving it one way or the other.”
While Walker was initially concerned with the progress of the pregnancy, he said that “the growth rate of both babies was good, which was reassuring.
When he gave the diagnosis to Roberts and his partner, Rhys Weaver, 43, “it was a huge shock,” said Roberts, who also has a 15-year-old daughter. “We got home and went straight to Google.”
Surfing the web, she said, has proven to be futile for the most part, as there is little research and few examples of successful superficial pregnancies online. The condition is so rare that the alleged cases are sometimes greeted with cynicism.
“There is very little information because it is not supposed to be happening,” Weaver said. “It was just crazy news.”
Over time, however, the notion of carrying two separately conceived babies began to normalize, Roberts said. While this might not be the pregnancy she expected, after years of yearning for another child, she was overjoyed to have not one, but two on the way.
Considering the rarity of the disease, coupled with Roberts’ age and the common risks associated with carrying twins, pregnancy posed some challenges, especially in the third trimester. The couple were told the youngest baby may not survive.
“Anything that can go wrong with a pregnancy is more common with twin pregnancies. But with a three week difference, you don’t want to jeopardize the smaller twin by delivering too early. You have to keep a very careful eye, ”Walker said. “Delivery was crucial in this case.”
Roberts knew preterm delivery was likely, so making sure the little baby was far enough advanced before birth “was a really huge concern for us,” she said.
At just over 33 weeks pregnant, the umbilical cord of the smaller fetus was not functioning normally, which began to impact the baby’s growth. The doctors decided it was time to give birth.
Although Roberts’ children technically have different due dates, she had a C-section and gave birth to both babies on September 17. Noah arrived first, weighing 4 pounds and 10 ounces. Two minutes later, her younger sister, Rosalie, arrived, weighing 2 pounds and 7 ounces.
“We got to see them both from birth,” said Roberts. “It was absolutely beautiful.”
“One of the best feelings I’ve ever had,” Weaver said.
The family’s initial bonding time was short, as both babies were taken to the neonatal intensive care unit. Noah was in the hospital for just over three weeks, while Rosalie stayed for 95 days.
The couple went to the hospital every day to visit their children, until just before Christmas, when they were given the green light to bring Rosalie home.
“We could finally go on and start our lives. It was like we were waiting to have them in the hospital, ”said Roberts, who designs children’s clothing.
Caring for twins, who are now almost 6 months old, has been a whirlwind, especially during the pandemic lockdown and while working from home. But Roberts said it made her heart fall to see the babies grow and develop over the past few months.
“Even though they were born on the same day, there is definitely an age difference between them,” she added. “It’s noticeable.”
Rosalie is still much shorter and less advanced than her brother, “but she’s catching up with him quickly,” said Weaver, a mortgage advisor.
Regardless of their developmental differences, however, their twin bond is undeniable, the couple said.
“When we put them next to each other on their play mat, they are looking at each other, reaching out, touching and talking to each other as well,” said Roberts. “It’s so beautiful to watch.”
Roberts and Weaver have documented the growth of the twins over the past few months on an Instagram page, and thousands of people around the world, fascinated by their story, are following them.
“We want people to be able to continue watching as they grow up,” said Roberts. “Miracles can happen, and my children are proof of it.”