After struggling with infertility for over a year, Rebecca Roberts welcomed her twins in a rare case of "superfetation."

Rebecca Roberts from Wiltshire, England, and her husband Reece Weaver had been trying to conceive for over a year when a medical wonder happened. At 39 years old, Rebecca was thrilled to see a positive pregnancy test report at home. During her first sonogram, her doctor confirmed she was pregnant with one baby.

But five weeks later when Rebecca went for her 12-week sonogram, things took a surprising turn. The sonographer noticed that instead of one baby, she was carrying two! One baby was noticeably less developed than the other one. Rebecca said in an interview, "The sonographer looked at me and was like, 'Do you know you're expecting twins?'"

However, this was quite an irregular "twin" pregnancy. It seemed that the second baby had miraculously appeared in Rebecca's womb a few days later. Rebecca was diagnosed with superfetation, a very rare case where a woman continues to ovulate even after getting pregnant, and the egg gets fertilized and implanted in the uterus.

According to a report published in 2008 by the European Journal of Obstetrics and Gynecology and Reproductive Biology, less than 10 superfetation pregnancies are recorded around the globe. After running multiple scans, Rebecca's doctor David Walker confirmed her rare pregnancy and said he had never witnessed superfetation in his 25 years of medical practice.

“Rebecca’s pregnancy is one of the very few superfetation cases recorded in medical history. This does not happen ... I have to scan several times so that I can confidently say superfetation. We were worried because the second of the twins was very young. By scanning regularly and keeping an eye on the rate of increase, we were able to know that he was exactly three weeks younger … and then confirmed that this is a case of superfetation, ” said Walker, an obstetrician at Royal United Hospital in Bath.

Usually, during pregnancy, a woman's body undergoes hormonal changes that stop further ovulation. "Instead of stopping ovulation, she released another egg about three or four weeks after the first one, and the egg somehow miraculously managed to fertilize and implant in her uterus," said Walker.

On September 17, 2020, Rebecca underwent cesarean section and delivered a son, Noah, who weighed 4 lbs. 10 oz, and a daughter, Rosalie, who weighed only 2 lbs. 7 oz. Rosalie had stopped growing in the uterus due to an issue with the umbilical cord, and both the babies were delivered at 33 weeks gestation. Both the twins, born two minutes apart, had to stay at the neonatal intensive care unit (NICU). While the elder twin Noah stayed for three weeks, Rosalie had to stay for 95 days before going home.

"When we lay them down next to each other, it's like they instantly know—and they reach out and touch each other's faces, and it's just the most beautiful thing," said Rebecca. "Twins have an amazing bond anyways, but the story between these two, when they're old enough to find out, they'll feel even more special."

While doctors are still not sure how Rebecca's superfetation happened, there is a possibility that a fertility drug she was taking may have triggered the ovulation of the egg even after Rebecca conceived.

Noah and Rosalie are now happy and healthy 6-month-old twins. They also have a 14-year-old sister, Summer. Rebecca continues to share their development on social media.

“We want people to be able to continue to watch as they grow up. Miracles can happen, and my children are proof of that.”

The last case of superfetation was reported in 2016 when an Australian woman became pregnant twice in 10 days. She delivered twin girls 10 days apart!

Do you have stories of rare pregnancies to share? Let us know in the comments.