FARGO - North Dakota passed a milestone recently by exceeding 10,000 births, a benchmark that last was reached almost 25 years ago.

The moment happened in 2012, when 10,072 resident births were recorded. North Dakota last surpassed 10,000 births in 1988, when 10,111 babies were born.

North Dakota again exceeded 10,000 births in 2013, although the official figure has yet to be compiled.

“We’re going through a bit of a baby boom,” said Kevin Iverson, manager of the North Dakota Census Office. “It’s going to continue to go up.”

The reason, Iverson and others said, is North Dakota’s sustained economic boom, which is luring people to the state, especially young people.

“Economic boom begets baby boom,” said Verlin Hinsz, interim director of the Center for Social Research at North Dakota State University.

“If you’re economically insecure, you’re less likely to have children,” he said.

It’s interesting that North Dakota dipped below 10,000 births per year in 1989, Hinsz said, noting the state was finishing a punishing decade marked by a farm crisis, an oil bust and severe drought.

“The ‘80s were horrible,” Hinsz said. “Basically, North Dakota was in a recession.”

As a result of the economic hardship, North Dakota saw a dramatic exodus of young people, an out-migration that lasted until the state’s economy began its recent boom.

North Dakota’s median age, 36.1 in 2012, fell from 37 two years earlier, reflecting the influx of young people. The state also has the largest proportion of 20- to 24-year-olds in the nation, almost 9.3 percent.

That’s a dramatic departure from recent decades.

The annual number of births in North Dakota peaked in 1954 at 17,432, during the post-World War II baby boom, and generally declined since then, except for an uptick in the late 1970s and early 1980s.

The number of births dropped below 10,000 in 1989, with 9,566 births that year. Births slowly but steadily declined through 2002, when 7,635 births were recorded.

A gradual increase began in 2003, with a sharp rise between 2011 and 2012, when births jumped from 9,234 to 10,072.

Last year, North Dakota had more than 11,000 births, said Carmell Barth, vital records research analyst for the North Dakota Department of Health.

But the official tally won’t be ready for several months. The unofficial total includes births from nonresidents. Still, Barth said, North Dakota will exceed the 10,000 mark in 2013.

The recent increase in births has occurred throughout most of the state, but is most pronounced in the west. Births essentially doubled in many Oil Patch counties from 2002 to 2012.

A few examples of western “baby boom” counties:

-- McKenzie County, which includes Watford City, had 59 births in 2002 and 114 in 2012.

-- Mountrail County, which includes Stanley, had 81 births in 2002 and 160 a decade later.

-- Stark County, which includes Dickinson, had 242 births in 2002 and 398 in 2012.

Dr. Tom Arnold, who heads the women’s clinic at St. Joseph’s Hospital and Health Center in Dickinson, said the jump in births coincided with the oil boom taking off five or six years ago.

“With that, we’ve had an uptick of people in the area. We have a lot of out-of-state patients coming to our delivery rooms.”

That can present more complications, including women who have lapses in their prenatal care or women who have gone without care.

“Sometimes their first prenatal visit is in labor-delivery,” Arnold said. “That’s been somewhat challenging. There’s an increase in complication rates, but, for the most part, it’s a manageable thing.”

St. Joseph’s, which is building a new medical center, will add another labor-delivery room to accommodate the increase in births.

Trinity Health in Minot and Mercy Medical Center in Williston also are increasing their birth center capacities to handle the significant increase in births.

All three medical centers treat patients from surrounding communities, where smaller hospitals no longer provide delivery care.

Leona Lambert, obstetrics manager at Mercy Medical Center, said the hospital recently delivered 11 babies in two days, and now averages about 60 per month, double the number five years ago.

“We used to see 11 babies in half a month,” she said.

“It’s busy,” Lambert added. Mothers at Mercy delivered 585 babies in 2012 and 746 last year, an increase of 27.5 percent.

Although the number of births also has increased significantly at Minot’s Trinity Health, the rise in cases at the neonatal intensive care unit has been more gradual, said Randy Schwan, a vice president at the medical center.

Births at Trinity have risen from 1,323 in 2010 to 1,629 last year, or 23 percent. “We’re anticipating that the growth is going to continue in the future,” Schwan said.

Hinsz agrees that North Dakota will continue to see a healthy birth rate, stemming from its vibrant economy.

“If you have a steady increase in population, this is just a natural consequence,” he said. “It’s a return to the natural pattern.”