Katelyn Yates, a 20-year-old nursing assistant from Illinois, went to the hospital on April 1 for a sore throat but left with astonishing news: she was pregnant with quadruplets. In an interview with Today, Yates recounted how her visit began with pain in her throat, leading doctors to recommend an X-ray.

Before proceeding, however, she had to take a pregnancy test, as radiation could be harmful to a fetus.

When the test results arrived, Yates learned that her hCG levels—the hormone produced during pregnancy—were “off the charts.” “I was completely in shock,” she said, initially thinking the doctor was playing a prank on her due to the date being April Fool’s Day. Her fiancé, Julian Bueker, 21, who had been dating her for just six months, was thrilled and helped keep her calm.

As the pregnancy progressed, Yates faced complications and was eventually diagnosed with preeclampsia, which causes high blood pressure after 20 weeks. She described struggling to breathe and experiencing liver and kidney issues during her third trimester.

On October 17, at 28 weeks and 4 days, Yates gave birth to quadruplets—Elizabeth Taylor, Zya Grace, Max Ashton, and Elliot Ryker, the latter two being identical twins. The babies were delivered via C-section at HSHS St. John’s Hospital in Springfield, Illinois. Elizabeth was the smallest at 1 lb., 2 oz., while Max weighed 2 lbs., 6 oz.

Today, Yates reports that all four babies are doing remarkably well, gaining weight and growing. “It’s amazing how well they are doing,” she said, noting that Elizabeth is just six grams shy of reaching 2 lbs. “Just a few weeks ago, they were the size of my hand.”