Teen births in the US hit an all-time low in 2015, but rural parts of the country haven’t experienced as big of a decline as larger cities and metro areas.

New federal data shows that from 2007 to 2015, the teen birthrate fell by 48 percent in urban counties. In rural counties, the teen birthrate fell 37 percent — still a remarkable decline, just not quite as significant as the change in cities.

"For all of the areas — rural, large, medium, small — they’ve all declined across the board," said Brady Hamilton, one of the authors of the report. "What’s interesting, though, is that it is immediately apparent looking at the classifications that there are still differences. Teen birthrates in the rural areas are noticeably higher."

Teens in urban areas now actually have a birthrate lower than the national average. But this isn’t true of rural counties, where there were still 30.9 births for every 1,000 teenage girls in 2015.

There are many more states now with urban counties experiencing a 50 percent or greater decline in teen birthrates, compared with states with rural counties going through the same change. You can see this in the maps below.

Limited access to contraceptives, poverty, and a digital divide may be why the teen birthrate isn’t declining as fast in rural counties

The National Campaign to Prevent Teen and Unplanned Pregnancy issued a 2015 report trying to explain why the urban-rural disparity in teen birthrates exists — and might be getting worse.

What it found was teens in rural areas have reduced access to health services, namely public clinics that offer free or subsidized contraceptive methods. Rural populations also have higher uninsured rates and are more likely to be in poverty. And rural teens might face transportation barriers and a gap in access to online resources.

"I think the reasons for this are pretty aligned to access issues," said Ginny Ehrlich, chief executive of the National Campaign. "We know that information and actual contraceptive services are more limited in rural areas, and people who live in more urban areas tend to have better access to contraception."

What’s next in studying the rural-urban divide in the teen birthrate

The NCHS plans to study if there is a difference in the teen birthrate between younger and older teens living in urban and rural counties. It will also analyze teens who report a second teen birth to see if a geographical gap exists between teens in urban and rural areas.