The neonatal ICU staff at an Ohio hospital is working hard after seven sets of twins were born within just one week. 

The Cleveland Clinic’s Hillcrest Hospital in Mayfield Heights shared an updated on Facebook earlier this month about how busy their NICU and postpartum units had been after seeing an unusually large number of twin births within just days of each other.

“We’ve been feeling double the love caring for 7 sets of newborn twins, at the same time,” the hospital wrote in the post, alongside snapshots of some of the twins and families. “Some parents welcomed their first babies, while others like Jason and Kara expanded their now family of seven! Best wishes to all!”

Local ABC affiliate News 5 Cleveland interviewed several nurses and other members of the hospital’s staff, who said that while they’re used to caring for a lot of patients at once, seven sets of twins at one time is almost a hospital record.

“How are we gonna get them all done?” Nurse Karoline Ferencak said she wondered. “Because we had ‘boom, boom, boom.'”

Nurse Halle Wedler added, “We had a great team on, and we had a good plan, and everyone kind of knew the plan, and we kind of just went for it and got them all delivered, and we racked them out.”

The outlet reported that only one set of twins was a boy and a girl. The rest were either boy-boy or girl-girl. Shannon Holz, a new mom from Shaker Heights, Ohio, welcomed the pair of boy-girl twins.

“We didn’t think we were gonna have twins,” she told reporters. “It’s a blessing at the end of the day, and we’re very happy to have these two healthy babies.”

While 14 babies at once is certainly a lot, the hospital told the news outlet that its record is nine pairs of twins at once. 

“We like to say, ‘Not double the work, double the fun.’ Honestly the workload has been great with them,” nurse Jessica Cunningham said. “We do a NICU reunion every year, so it would be really cool for all these families to come back just to see how big they are, because this is something we don’t see very often.”

Just how common are twin births?

Per the Centers for Disease Control And Prevention, in the United States, the twin birth rate was 31.2 per 1,000 live births in 2022, which is equivalent to 114,483 twin births. This is a 72% increase from 1980, when the rate was 18.9 per 1,000 births. However, the rate of twin births varies across populations. 

It’s estimated that 1 in 250 pregnancies results in twins naturally. The chances of having identical twins is pretty rare—around 3 or 4 in every 1,000 births. Identical twins are always the same sex, either both boys or both girls, at birth as they also share the exact same DNA. Fraternal twins, however, result when two separate eggs are fertilized by two separate sperm cells. Both fertilized eggs implant into the uterus and—9 months later—two babies are born.

The chance of having twins is higher for people who have used assisted reproductive technology, such as in vitro fertilization (IVF). The likelihood of having twins may also increase with age, with women aged 35–37 having a 6.9% chance, and women aged 43 and above having a 5.9% chance.