There's no set ideal for how close a pregnant woman should live from a maternity hospital. And the study did not look at whether women living more than an hour's drive away face bigger risks.

But researchers say the findings add to the issue of Americans' varied access to medical care -- which, not surprisingly, is much more limited in rural areas than urban or suburban ones.

The study, reported in the journal Obstetrics & Gynecology, found that just over 97 percent of U.S. women ages 18 to 39 live within an hour's drive to a hospital with at least basic maternity and nursery care.

Fewer women -- 80 percent -- are that close to hospitals fully equipped to handle complicated deliveries and sick newborns, which includes running a neonatal intensive care unit.

But the numbers varied based on where women lived.

Women in the Northeast had the easiest access. In states like New York, New Jersey, Connecticut and Pennsylvania, more than 99 percent of women lived within an hour's drive of a hospital with maternity care. And the vast majority were within a 30-minute drive.

The situation was similar in California, where 98 percent of women had an hour's drive or less to the nearest center.

But out in the "non-coastal" Western U.S. -- where the population density is far smaller -- the situation was different. Women in Montana, North Dakota, New Mexico and Wyoming had some of the lowest access rates: anywhere from 68 to 84 percent were within an hour's drive of any hospital with maternity care.

The one state with a lower rate was Alaska, at only 63 percent.

"The difference is really dramatic," said lead researcher Dr. William F. Rayburn, of the University of New Mexico in Albuquerque. "There's a real dividing line."

There's been debate about what the "optimal distribution" of hospitals with maternity and newborn care really is, Rayburn and his colleagues note.

"But I think that ideally, no woman should have to drive more than an hour," Rayburn told Reuters Health.

So what is the solution? In rural areas with sparse populations, building new hospitals is unlikely to be a practical solution, the researchers say.

One alternative, Rayburn said, would be greater use of "telemedicine" -- where doctors at small, non-maternity hospitals can consult with ob-gyns at larger medical centers when they have a complicated case.

There's also a pool of doctors in rural areas who may not be ob-gyns, but could step in when a woman needs a C-section, for instance.

Rayburn's team found that there were 136 hospitals in rural areas of Western states that had no specialized maternity services, but did have general surgeons on staff.

Those community centers, Rayburn said, could make "provisions" to ensure that a general surgeon would be available should a women need an unplanned C-section.

As for what pregnant women in rural areas can do, Rayburn advised talking to your doctor.

"I think women need to talk with their provider about what kinds of provisions there will be if she has to deliver quickly," he said.

And if a woman has a high-risk pregnancy -- like a twin or "higher-order" pregnancy -- she may need to schedule a labor induction at the nearest medical center, instead of waiting for Mother Nature.

The issue of drive time from specialized, emergency medical care is not a new one, Rayburn pointed out. People in the rural U.S. can also live far from centers fully equipped to treat heart attacks or strokes, for instance.

"This is not a novel issue in medicine," Rayburn said.

SOURCE: bit.ly/xou4lf Obstetrics & Gynecology, March 2012.

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