(CNN) -- A Utah couple whose journey through in-vitro fertilization captivated the nation welcomed quadruplets -- two sets of identical twins -- Sunday.
Ashley and Tyson Gardner said they are "overwhelmed with joy" after the birth of Indie, Esme, Scarlett and Evangeline by Caesarean section at Utah Valley Regional Medical Center in Provo. Three of the newborns weighed a little more than 2 pounds at delivery. The fourth weighed slightly less than 2 pounds, according to the hospital.
The Gardners announced the news on the Facebook page where they share news about the pregnancy.
"Mom and babies are doing incredible!!! We are so happy with how everything turned out today! The doctors, nurses, and staff were incredible!! More updates to follow soon!!"
The Pleasant Grove couple conceived two sets of identical twins this summer with the help of in-vitro fertilization. In October, Ashley Gardner had emergency laser surgery in California to save one set suffering from twin-to-twin transfusion syndrome, the hospital said in a news release. She began staying in an antepartum suite at Utah Valley Regional in November after doctors decided hospital bed rest was necessary.
The four girls, dubbed the "Quad Squad" by the hospital, were due March 11. Doctors decided to deliver them 12 weeks early after discovering that Ashley Gardner had ruptured some membranes and her contractions continued to progress in intensity, the hospital said.
Complications leading to premature delivery are common in multiple gestations, whether achieved naturally or though IVF, said Dr. Andrew Toledo, CEO of Reproductive Biology Associates in Atlanta, the largest IVF program in the Southeast. But data show that women who achieve pregnancy through IVF have a slightly higher rate of complications compared with patients who conceive naturally.
It's also extremely rare for both embryos to split, but it's more common in IVF pregnancies compared with patients who conceive naturally, he said.
In a YouTube video posted Sunday morning from the hospital, Tyson Gardner said that mom and the babies were doing well after a night in the hospital and that they expected the quads to come in the next couple of days.
"We need lots of prayers the next 48 hours," Ashley Gardner said from her hospital bed.
The Gardners tried for years to get pregnant. Finally, they learned in July that their first in-vitro fertilization attempt was successful. But the real surprise came during the ultrasound, when they learned she was pregnant with quadruplets.
A friend in the room captured the priceless look on her face in a picture that took the Internet by storm. In one week, the Gardners' Facebook page grew by nearly 16,000 likes to 24,300. Today, it has almost 300,000 Facebook fans, and the TV network TLC is following them for a series set to air in 2015.
Well-wishers flooded their Facebook page Monday with congratulations and requests for pictures.
"Congratulations," one person said. "Wishing you health and happiness for many years to come."