SALT LAKE CITY » A pregnant Utah woman driving herself to the hospital gave birth to a healthy, nearly 10-pound baby boy on the side of an interstate highway, police said.

Devi Mariah Ostler’s labor started Saturday before she got in the car, but soon became overwhelming and she called 911, Utah Highway Patrol Trooper Jalaine Hawkes said.

On a recording of the call, Ostler is initially calm, telling the dispatcher that she’s on the freeway, but soon interrupts herself to say her water broke.

"I’m trying to get over into the other lane — I need to push!" she said. She told the dispatcher her name and described her car, then said: "The baby is coming!"

The 32-year-old expectant mother pulled over on the side of Interstate 15 as dispatcher Brittney Chugg talked her through the labor, telling her to lay her seat back, breathe and even hold the baby’s head so he wasn’t born too fast.

"We knew. We just knew it was going to happen. There was going to be a baby on the side of the freeway right then," said Chugg at a news conference Sunday, according to the Deseret News.

Police Chief Jean Loveland from the nearby town of Willard and Utah Highway Patrol trooper Josh Carr sped to the spot. Less than a minute after their arrival, she gave birth to a 9.9-pound baby boy. Cars can be heard speeding by on the recording as the baby is born and wrapped in a sweat shirt.

"He came right out in my hands," said Carr, who told her the gender of the baby for the first time. "It was very emotional. Probably next to my own children’s’ birth, it was a very satisfying moment in my career."

He is her third child.

Ostler, of Mantua, said the contractions started as she was driving her 6-year-old son at her mother’s house, and when they didn’t stop she started driving herself to the hospital.

"I knew the baby was coming and it doesn’t help to panic. So, I just stayed calm and said, ‘Well, if I deliver it on my own then I deliver it on my own. If somebody gets here, somebody gets here. The baby is here. There’s not much more I can do about it,’" she said Sunday.

She had not picked a name for the baby as of Sunday.

The mother and baby were taken in good condition to the hospital in Brigham City, about 60 miles north of Salt Lake City.

"Everyone is really feeling good," Hawkes said. The baby was due on Tuesday.

Roadside births happen occasionally in the state, especially in rural areas where it’s harder to get to a hospital quickly, Hawkes said.

Troopers are all equipped with a delivery kit, and when babies are born healthy it’s a happy occasions for emergency crews as well.

Another Utah woman gave birth to twins on the side of Interstate 80 in June 2013.

In that case, 39-year-old mother Lynette Hales was 30 weeks pregnant and taking a last getaway in the Nevada gambling town of Wendover near the Utah border when she went into labor. The first baby had difficulty breathing at first, but both baby boys were flown to a hospital in fair condition.