Kelly Fairhurst and her partner, Joshua Boundy, were shocked when they discovered they were expecting another child.
Little did the UK-based parents know, they were about to get an even bigger surprise.
At Fairhurst’s 12-week pregnancy scan, she learned she's carrying two babies — twins — in separate wombs.
“My midwife looked at me and said, ‘In 30 years I’ve never seen anything like this,’” Fairhurst, 28, told TODAY Parents.
What Fairhurst has is a rare medical condition called uterine didelphys. According to Dr. Ashley Roman, director of the Division of Maternal Fetal Medicine at NYU Langone Health, it occurs in less than 1% of women.
“Put simply, uterine didelphys is when a woman has two uteri, both of them smaller than the size of a normal uterus,” Roman told TODAY Parents.
Roman noted that what makes Fairhurst’s case so unique “is the fact that there is one fetus in each uterus.”
Fairhurst and Boundy, who are already parents to daughters, Agyness, 4, and Margot, 3, are technically due in November. But they understand that the babies will likely come much earlier.
Fairhurst said her doctors in London are hoping to get her to the 28-week mark. (A pregnancy is considered full-term at 39 weeks.)
“Women with uterine didelphys have a higher risk of preterm labor (and) preterm birth,” Roman said. There’s also a change one or both of the fetuses will not grow well. Experts believe the risks are related to the smaller size of each uterus.
Fairhurst's twins are likely fraternal twins, each growing from a separately fertilized egg. "The most likely scenario is that ovulation occurred twice," Roman said, although adding that her experience in obstetrics has taught her to "never say never!"
"I’m constantly surprised by human biology," she said.
Though it's possible Fairhurst could go into labor twice, it's highly unlikely, according to Roman.
“While we don’t understand all of the processes that initiate labor, there is a strong hormonal component in that a number of different hormones that circulate in the bloodstream seem to be an important trigger,” Roman said. “Once these various hormones are released into or withdrawn from the bloodstream, the effect would be on both uteri.”
But Fairhurst isn't taking any chances. She plans to have a scheduled Cesarean section.
"We're doing it for safety reasons," she said.
Recently, Fairhurst started an Instagram page to connect with other women with uterine didelphys.
“I was reading a lot on the internet about people losing one or both babies, which was of course upsetting," Fairhurst told TODAY Parents. “But now I have people messaging me their success stories."