Story highlights The quintuplets' mother was using injections to help her conceive

The three boys and two girls are in stable condition

Doctors say they're likely to remain hospitalized for several months

A team of more than 50 specialists assisted with their births

Their mother calls them "five tiny bundles of perfection."

The quintuplets -- among the first set delivered nationally so far this year -- were in stable condition after being born Thursday to missionaries Carrie and Gavin Jones at the University of Texas Southwestern Medical Center in Dallas

Three boys and two girls -- Will Edward, David Stephen, Marcie Jane, Seth Jared and Grace Elise -- remained in the neonatal intensive care unit at St. Paul University Hospital, part of the medical center.

While in stable condition, the siblings likely will remain hospitalized for several months until they reach weight, post-birth age and health markers.

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"The five babies are doing quite well right now," Dr. Gary Burgess, medical director of the hospital's neonatal intensive care unit, said Monday. "They're doing as expected. We always have little issues in the first week of life with these infants. ... They're very stable right now."

The five ranged in weight at birth from 1 pound, 12 ounces to 2 pounds, 11 ounces and in length from 12.5 inches to 15.5 inches.

"For all the anxiety that a quintuplet pregnancy generates, Carrie and Gavin are the perfect couple of have held it together," said Dr. Patricia Santiago-Munoz, who delivered the babies in less than five minutes, according to the hospital. "A birth like this takes a village."

That it did -- a team of more than 50 specialists, nurses, therapists and technicians assisted Santiago-Munoz, an assistant professor of obstetrics and gynecology.

Medical teams planned for the births for months, even designating a special "Code 5" designation, handing out pagers to staff and developing a color-coded system to match each baby with his or her needed supplies. Weekly drills were held to prepare for the births, the hospital said.

"Even though I was the one responsible initiating that code, I just thought it was so exciting, and I think everybody felt it last Thursday morning," Santiago-Munoz said Monday.

On average, about 12 sets of quintuplets are born each year, according to the hospital. In 2009, the Centers for Disease Control and Prevention recorded 16 sets

Gavin Jones, 35, is a helicopter pilot. He, his wife and the couple's 8-year-old son Isaac are missionaries in the South Pacific nation of Papua New Guinea.

Carrie Jones said Monday she had been using injections to help her conceive, but the couple did not undergo in vitro fertilization, which sometimes results in multiple births.

"Isaac's been praying for five years for a sibling, and so I fully blame him," she said. "... These five were a huge surprise."

Her husband said, "The intent was to have one."

Carrie Jones said she isn't sure when they will return to Papua New Guinea.

"We'd like to ideally go back in July so we can get Isaac started in third grade, but we'll just see how the babies are. ... Right now that's our biggest priority," she said.

The couple chronicled the pregnancy and documented the babies' births on their blog , and continue to offer updates on the babies' medical conditions and progress.

Seth, for instance, has battled breathing difficulties, his parents said. "Seth's left lung is better," according to a Sunday blog post. "Now they are trying to inflate his right lung."

Seth is on a special ventilator but is doing well, Burgess said Monday.

Three of the babies -- Will, David and Marcie -- are on nasal prongs, which provide them with continuous positive airway pressure, Burgess said. Doctors hope to remove those within the next two days.

Grace is on a mechanical ventilator but is "very stable," he said. The other four were receiving intravenous and oral nutrition.

Each baby is assigned his or her own medical team, the hospital said, including a neonatologist, neonatal nurse practitioners, nurses, respiratory therapists, pharmacists and radiology technicians.

The Joneses said on their blog that it's "an emotional time" and "with five babies at different stages of wellness, it's quite a roller coaster around here."

"I am so in love with these five tiny bundles of perfection," Carrie Jones posted. "Obviously, my favorite times of the day are those I spend in the NICU."

Gavin Jones said in a statement, "We have been blown away by the outpouring of prayers and support for us through this unexpected journey. We are especially grateful to the team of professionals at UTSW who have gone beyond the call of duty in preparing for the babies and caring for Carrie. They have been amazing."