WASHINGTON (AP) -- Most women who've had a C-section, and many who've had two, should be allowed to try labor with their next baby, say new guidelines -- a step toward reversing the "once a cesarean, always a cesarean" policies taking root in many hospitals.

Wednesday's announcement by the American College of Obstetricians and Gynecologists eases restrictions on who might avoid a repeat C-section, rewriting an old policy that critics have said is partly to blame for many pregnant women being denied the chance.

Fifteen years ago, nearly 3 in 10 women who'd had a prior C-section gave birth vaginally the next time. Today, fewer than 1 in 10 do.

Last spring, a National Institutes of Health panel strongly urged steps to reverse that trend, saying a third of hospitals and half of doctors ban women from attempting what's called VBAC, for "vaginal birth after cesarean."

The new guidelines declare VBAC a safe and appropriate option for most women -- now including those carrying twins or who've had two C-sections -- and urge that they be given an unbiased look at the pros and cons so they can decide whether to try.

Women's choice is "what we want to come through loud and clear," said Dr. William Grobman of Northwestern University, co-author of the guidelines. "There are few times where there is an absolute wrong or an absolute right, but there is the importance of shared decision-making."

Overall, nearly a third of U.S. births are by cesarean, an all-time high. Cesareans can be lifesaving but they come with certain risks -- and the more C-sections a woman has, the greater the risk in a next pregnancy of problems, some of them life-threatening, like placenta abnormalities or hemorrhage.

The main debate with VBAC: That the rigors of labor could cause the scar from the earlier surgery to rupture. There's less than a 1 percent chance of that happening, the ACOG guidelines say. Also, with most recently performed C-sections, that scar is located on a lower part of the uterus that's less stressed by contractions.

Of those who attempt VBAC, between 60 percent and 80 percent will deliver vaginally, the guidelines note. The rest will need a C-section after all, because of stalled labor or other factors. Success if more likely in women who go into labor naturally -- although induction doesn't rule out an attempt - and less likely in women who are obese or are carrying large babies, they say.

Thus the balancing act that women and their doctors weigh: A successful VBAC is safer than a planned repeat C-section, especially for women who want additional children -- but an emergency C-section can be riskier than a planned one.

Because of those rare uterine ruptures, the obstetricians' group has long recommended that only hospitals equipped for immediate emergency C-sections attempt VBACs. Many smaller or rural hospitals can't do that, and that recommendation plus high-dollar lawsuits have been blamed for some hospital VBAC bans.

"Restricting access was not the intention," the new guidelines say. They say hospitals ill-equipped for immediate surgery should help women find care elsewhere, have a plan to manage uterine ruptures anyway, and not coerce a woman into a repeat C-section.

Educating women about their options early enough in pregnancy for them to make an informed choice is key, said Dr. F. Gary Cunningham of the University of Texas Southwestern Medical Center, who chaired the NIH panel on repeat C-sections.

It requires a fair portrayal of risks and benefits that can differ by patient, added Dr. Howard Minkoff of Maimonides Medical Center in Brooklyn, N.Y., which has women sign a special VBAC consent after counseling yet has a higher-than-average VBAC rate of 30 percent.

"There's no doubt that how things get framed influences how people act," he said.

While the guidelines cannot force hospital policy changes, some women's groups welcomed them.

"I feel like ACOG has really listened to how their previous policies have impacted women," said Barbara Stratton of the International Cesarean Awareness Network's Baltimore chapter, adding that she'll advise women seeking a VBAC to hand a copy of the guidelines to caregivers who balk.

But she called for reducing overuse of first-time C-sections, too, so that repeats become less of an issue.

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