Hospital Welcomes Second Set of Rare 'Mono Mono' Twins

One week after welcoming a set of "mono mono" twins that were born holding hands, an Ohio hospital has delivered a second pair of the rare babies.

Amanda Arnold, 24, gave birth to identical twin daughters Thursday at Akron General Hospital in Akron, Ohio. The girls were monoamniotic or "mono mono," which means they shared an amniotic sac and placenta in the womb. Experts say the rare condition affects roughly one in 10,000 pregnancies.

"If they can hold hands too, that would be great." Arnold told ABC News affiliate WEWS-TV before the birth, referring to the viral photo of monoamniotic twin girls born one week earlier at the same hospital. "I'm ready to meet them."

Rare Set of Twins Hold Hands in Delivery Room

Dr. John Stewart, director of maternal and fetal medicine at Akron General Hospital, said the chance of two sets of monoamniotic twins being born at the same hospital is "probably in the order of one in a million to one in ten million."

It took doctors only 19 minutes to deliver the twins via cesarean section. (NewsNet5)

Stewart added that the rare twins are usually scheduled for delivery between 32 to 34 weeks to avoid complications like becoming entangled in each other's' umbilical cords.

"The babies can cut of their blood supply to each other," Stewart told ABC News.

Arnold was hospitalized for five weeks before the delivery so that doctors could monitor the twins' blood supply. She gave birth by C-section at 32 weeks.

The rare set of twins shared an amniotic sac and placenta. (Image credit: NewsNet5)

While the girls didn't emerge holding hands, Arnold said they gave their lungs a workout with a healthy cry.

"I just got a glance, they were so little," Arnold said of seeing her daughters for the first time.

The girls are being treated at Akron Children's Hospital, where they will remain for several weeks until they grow bigger and stronger.

Arnold said she expects life will be significantly different when the girls finally get to go home.

"I'm pretty sure it's going to change a lot after tonight," she told WEWS-TV. "I'm definitely sure of that."

Another pair of "mono mono" twins held hands after being born. (Courtesy Akron Children's Hospital)