(CNN) – At first, Noah was alone and was growing well in his mother’s womb.
The first images of Noah were taken with ultrasound between 7 and 10 weeks after the pregnancy and showed Rebecca Roberts, 39, and Rhys Weaver, 43, the baby they had been trying to conceive for over a year.
When Noah was three months pregnant, he was joined.
An ultrasound made in week 12 showed that Noah had an unexpected little sister, his fraternal twin, Rosalie.
“I got pregnant when I was already pregnant, which was crazy … because that shouldn’t happen,” said Rebecca.
It’s called superfetation when a second baby is conceived while already pregnant, and it’s such a rare condition that a 2008 study found there are fewer than 10 recorded cases worldwide.
Doctors told the couple that the babies were conceived three weeks apart, Rebecca said.
“They realized that the baby was constantly growing three weeks less than the first, and then they told me they thought it was a super-perfect pregnancy,” he said.
“I couldn’t believe it had happened to me,” Rebecca added, smiling. ‘But it happened, it is beautiful. It’s like winning the lottery. “
The father felt the same: “I was happy with a son, but especially for the twins. The job is done in one go! And then Rebecca did some research and we realized how unique and happy we were. “
An incredibly rare event
Superfetations are rare for a variety of reasons, noted Atlanta, Georgia-based gynecologist Dr. Lillian Schapiro on.
First, women generally ovulate only once per cycle, releasing one or more eggs at the same time. If fertilization by the male’s sperm is successful, the egg or eggs will implant in the uterus, pregnancy will begin and no further ovulation will occur.
“When a woman has twins,” said Schapiro, “two eggs are released at the same time. And in the unusual case of triplets, those eggs are all released in a single ovulation. “Identical twins arise when a single fertilized egg divides.
In Rebecca’s case, the egg was fertilized and implanted during the first ovulation, and “somehow she ovulated again during that same cycle,” explained Schapiro. “Another egg was also fertilized – it became a different embryo – and both embryos were implanted in the uterus at different times.”
Another reason superfetations are rare, Schapiro said, is that once pregnancy begins, the uterus is no longer a welcoming place for implantation. That means that the second embryo “managed to implant and grow at a stage where we never thought it could.”
“We have almost never seen two embryos develop at different times,” said Schapiro. “That’s great.”
Before Rebecca became pregnant, she had just taken a dose of fertility drugs designed to stimulate ovulation. While that may be a reason for this rare event, Rebecca noted, it could also be just a “ medical miracle. ”
“Tiny, tiny baby”
Initially, Rebecca and Rhys were concerned about baby Rosalie’s development in the womb, fearing that standing behind her brother could affect her health at birth.
“It can go either way,” Rebecca said. “Because the baby is so much smaller, he may have a problem and may not survive. That is usually the case. However, they said this baby is constantly growing, ”he noted. “It was a relief. It was a great relief.”
Both babies, born by Caesarean section in September 2020, had to spend separate time in neonatal intensive care units (NICUs). Rosalie, who was born weighing 1.1 kg, was sent to a specialized NICU 15 minutes away from the NICU where Noah was, who was born weighing 2.09 kg.
“She was a little baby, small that would fit in our hands, and though he did [Noah] it was small, you could tell it was a much bigger baby, ”Rebecca said.
“It was very difficult. I had major surgery and then our babies were also taken to two different hospitals,” he said. “So it was very difficult to travel between the two.”
Noah was able to go home in three weeks, but little Rosalie was in intensive care for 95 days and managed to get home just before Christmas.
Now, at almost 7 months old, Noah Rosalie is still ahead, but Rhys commented, “She’s a little soldier. It has its own personality and I’m not worried. “
Noah can roll now and “he’s actually showing signs of crawling, so he can start soon, which will be nice,” added Rebecca.
“They both talk, which is nice because they talk to each other. It’s cute. They get along very well, very well. It is wonderful to see them ”.