A New York state mother is recovering after giving birth to a record 15-pound baby girl last week.

Harper Buckley came into the world weighing in at 15-pounds, 15-ounces and measuring about 23-inches long. She's the heaviest baby ever born at Arnot Ogden Medical Center in Elmira, N.Y., and she could be the heaviest baby ever born in the state.

"I knew she was going to be big but I didn’t anticipate no 15-pound baby," mom Joy Buckley told WETM.

Buckley calls Harper a "miracle baby," because the mom was once told by doctors she had about a 15 percent chance to conceive naturally after being diagnosed with polycystic ovarian syndrome, The Washington Post reports.

After years of infertility, Buckley became pregnant with a son, born at 11 pounds, and also decided to adopt.

On March 12, by way of a planned C-section that left her covered with bruises and a feeling of being "hit by two tractor-trailers simultaneously," Buckley and her husband welcomed their third child, The Washington Post reports. She was born the weight of an average 5-month-old.

Average birthrates are between 5.5 and 8.8 pounds, according to the U.S. National Library of Medicine.

Heavy babies do pose some health risks, including bleeding and delivery complications. Large babies also are more at risk of low blood sugar or an elevated blood count, which is often monitored in a neonatal all-intensive nursery.

More:Babies twice normal size have been in the news — how does a baby get so big? Is it safe?

The heaviest baby ever born in the U.S. weighed 22 pounds, according to Guinness World Records. He died 11 hours later.

Buckley and Harper appear to be doing well. Harper was placed in the NICU after birth to monitor sugar and oxygen levels but is expected to be released soon.

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