Mom just had a third set of back-to-back twins—for a total of 10 kids

Bringing home newborn twins means double the joy, double the work and probably lots of big surprises along the way. But for one mom in New York, the two new babies she recently delivered have a special distinction in the family: They are the third consecutive set of twins for this mother.

Kimberly Alarcon gave birth to fraternal twin daughters Kenzy and Kenzley on April 25 at the Westchester Medical Center in Valhalla, New York, according to Fox 5 New York. Kimberly and her husband, John, are well known to the hospital staff.

“They call me ‘the frequent flyer,'” Alarcon told “Good Morning America.” “I’ve been coming to labor and delivery at Westchester Medical now for 17 years. Every three years, there’s a baby.”

The staff at Westchester Hospital posted photos on its Facebook page of the babies and their mama, as well as information about how the Alarcon family has become part of the hospital’s family.

In addition to the two new babies, Kimberly and John have eight other children, including Brittney, 17, Sarah, 13, Hunter, 10, twins Zachary and Zoey, 6, and twins Oliver and Olivia, 4. They’re also fostering their 3-year-old nephew King, according to “Good Morning America.”

After two sets of twins, one would think the parents wouldn’t be surprised by a third. However, the new mom of 10 insists each pair caught the parents off-guard.

“It was shocking because, to be honest with you, we never planned,” the busy mom told Fox 5 NY. “Shocking every time. It was a shocker.”

How rare are three sets of twins born without fertility treatments? Dr. Angela Silber, chief of fetal medicine at Westchester Medical Center, told NBC’s “Today” that a number of factors contribute to conceiving twins without fertility drugs including advanced maternal age (35 years old or older), a history of twins on the mother’s side and a higher BMI. Still, Dr. Silber marveled at the trio of twins for the Alarcon family.

“But three sets of twins back-to-back without medication or any intervention is highly unusual,” she told “Today.” “It’s pretty incredible.”