Photo: @roberts.supertwins on Instagram
Exciting as they are, ultrasounds can be freaky—the technicians are often silent and unable to share what they're seeing. But when Rebecca Roberts had her 12-week scan, there was no way her technician could keep quiet after finding a second baby floating around in her uterus!
“I thought something awful had happened,” Roberts, of Wiltshire, England, told the Washington Post. “The sonographer looked at me and was like, ‘do you know you’re expecting twins?’”
Rebecca wasn't expecting twins, as far as she knew. In fact, she and her partner, Rhys Weaver, had been struggling with fertility issues, so finding out five weeks earlier that they were pregnant with just one baby was already a big surprise. But in a super rare phenomenon that's said to have been recorded less than a dozen times, according to the European Journal of Obstetrics & Gynecology and Reproductive Biology, it looks like this mom got pregnant while already pregnant. Her babies were conceived a few weeks apart.
“We were concerned because the second twin was much smaller," explained her obstetrician, David Walker. "It was only by regularly scanning and seeing that the rate of growth was consistently three weeks behind that we realized it was superfetation.”
It's so rare that in his 25 years of practice, Dr Walker had never seen it happen, and they did numerous ultrasounds before he was confident that this was the case.
"My initial reaction was, 'How had I missed the second twin?'" Walker told Good Morning America. "And following this [I] was slightly relieved that it was not my mistake but a quite extraordinary pregnancy."
Needless to say, not a lot of results came up when Roberts, who also has a 15-year-old daughter, went home and got to Googling.
"It just doesn't happen," Walker told the Washington Post. This is because when a woman gets pregnant, her body puts the breaks on conception (hormones are responsible for a lot more than those brutal mood swings). But somehow, not only did a miracle egg slipped through the cracks when ovulation was supposed to have stopped, but it also managed to fertilize and implant in her uterus.
He's not convinced that the fertility drugs Roberts was taking played a role in the superfetation. “She didn’t release two eggs at the same time, which is what the medication normally does,” explained Walker. “But we have no way of proving it one way or another.”
Like with all twin pregnancies, especially when the pregnant person is in their late 30s, the pregnancy had to be monitored closely, but the twins' special circumstances also meant making sure wee Rosalie, the younger baby, was able to develop enough to 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 compromise the smaller twin by delivering too early. You have to keep a really close eye,” said Walker. So the delivery was crucial, and they were able to hold off until Roberts was 33 weeks along, when an issue with Rosalie's umbilical cord had prevented her from growing.
On November 17, 2020, in a moment that Roberts describes as "absolutely beautiful," babies Noah and Rosalie made their debut via C-section, the big brother weighing in at 4 lbs 10 oz and his little twin sister a dainty 2 lbs 7 oz. After some time in the NICU, the duo is home and thriving.
“Even though they were born on the same day, there’s definitely an age difference between them,” Roberts noted. “It’s noticeable.”
But they're undeniably twins, with that special bond that only sharing a tummy can provide.
“When we lay them down next to each other on their play mat, they look at each other, reach out and touch each other, and talk to each other as well,” explained their proud mom, who has shared their journey on Instagram at @roberts.supertwins. “It is so beautiful to watch.”
Every time we think we've seen it all, from the mom with the double uterus who gave birth twice in 26 days to a video of a baby peeing in the womb, another unbelievable story comes along and makes our brains (and hearts!) explode. The human body is incredible—and so are Rebecca Roberts and her supertwins!
Keep up with your baby's development, get the latest parenting content and receive special offers from our partners