A Florida woman gave birth to twins,  Natalie and Nathan Barbosa, Sept. 15, but the newborns were born  from their mother’s two uteruses,  according to ABC affiliate WFTS.

Andrea Barbosa, 24, has a rare condition called didelphys — also called double uterus — that affects about one  in 2,000 women worldwide, doctors at Morton Plant Hospital said.

“I was shocked to learn I had a baby in each uterus,” Barbosa said in a hospital news release.

Nathan was born at 36 weeks and weighed 5 pounds, 8 ounces. His sister emerged two minutes later, weighing 5 pounds, 10 ounces.

The hospital said only about 100 women with this condition  carry fetuses in two uteruses at the same time.  Experts estimated  that only about  one in 5 million such pregnancies succeed.

In the 4 percent of women who have reproductive abnormalities, 5 percent have a double uterus.  Of those women, only about 3 percent are likely to conceive one child in each uterus, and  1 percent of those who do conceive  this way carry the babies to term.

Sarah Reinfelder of  Michigan also, like Barbosa, defied those long odds in 2009 when she carried twin girls in both her uteruses.  The girls were born seven weeks premature. Reinfelder had previously miscarried another set of twins two years earlier,  but later gave birth to a son.

“We know there’s a high rate of [problems] but it’s not known why,” Dr. Richard J. Paulson, chief of reproductive endocrinology and infertility at the University of Southern California Keck School of Medicine in Los Angeles, told ABC News after Reinfelder’s twins were born. “It’s not impossible, but it makes it more complex.” 

Barbosa’s doctors said they took extra care  throughout her pregnancy.

“Because we were aware of her condition, we were able to ensure that both mother and babies would be healthy,” said Dr. Patricia St. John, one of Barbosa’s doctors.

Barbosa, who also has a young daughter, said she’s grateful for the two extraordinary additions to her family.

“[M]y husband and I are just so happy that they are here and healthy,” she said.