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Many babies in breech position are still delivered vaginally, which increases their risk for complications, a new report warns.

Fewer breech babies are now born vaginally than 15 years ago, when a landmark study found that cesarean sections greatly reduced the risk of death for the baby.

But as of 2007, 40 percent of mothers in that situation still choose a vaginal birth, and the risks are still high, according to a new study.

In the safest vaginal birth, the baby turns and lies head-down in the pelvis before delivery. The head is the largest part of a baby, and when that comes first, the shoulders and body tend to slip right out rather easily, Dr. Lucy Chappell told Reuters Health.

But a “breech” baby does not turn and would emerge feet or butt-first. In that case, the head can get trapped, which can lead to birth complications.

There are some techniques to try to help the baby turn face down, but they don’t always work.

In 2000, a study from the Netherlands found that breech babies born vaginally had a 33 percent higher risk of injury or death compared to those born by C-section.

That study led to changes in maternal healthcare worldwide, with many more women and their doctors choosing C-sections, said Dr. James Byrne, chairman of the obstetrics and gynecology department at Santa Clara Valley Medical Center in San Jose, California.

He was not involved in the new research, nor was Chappell, who is a clinical senior lecturer in Maternal and Fetal Medicine at King’s College London.

The new study used data from The Netherlands on all babies born there, singly and not premature, between 1999 and 2007. Altogether that included 1.4 million deliveries, of which four percent, or nearly 60,000, were breech deliveries.

“The Dutch use both midwives and obstetricians and collect data really thoroughly in a very well organized way,” so these results are probably applicable to other developed countries like the U.S., Byrne told Reuters Health by phone.

In 1999, 24 percent of women with babies in a breech position planned in advance to have a C-section, which rose to 60 percent in 2007.

In the group that had planned C-sections, fewer babies died during birth or within the first 28 days of life as time went on. The death rate fell from more than 10 babies of every 10,000 in the earlier period, to seven babies in 10,000 in the later period.

Low Apgar scores and injuries to the baby during birth, including bleeding and broken bones, decreased as well.

For every 338 C-sections, one newborn death was prevented, according to the analysis in the medical journal Acta Obstetrica et Gynecologica Scandinavica.

Among women who still planned to try for a vaginal delivery, emergency C-section rates increased as well, from 34 percent to 45 percent.

But in the planned vaginal delivery group, the death rate stayed the same even after publication of the landmark trial, hovering around 17 babies out of 10,000.

“You would think that now, women planning vaginal births would have better outcomes, because only the best candidates would do it,” Byrne said. “But even in this group which is probably the safest group you would imagine, the risk of the baby being injured was still the same.”

The researchers tried to find a subgroup within the vaginal delivery group with lower mortality rates and safer outcomes – based on the number of babies the mother already had, specific breech position or birth weight – but could not.

That’s very disappointing news for Byrne and his colleagues, he said.

Chappell agreed that the new data have many strengths, but did note that there could have been something else unique to the women who still chose vaginal births that increased neonatal risks.

“The headline message is that Cesarean section looks like the way to deliver breech babies at term,” she told Reuters Health by phone. “But there’s a gap between policy and guidelines and recommendations and what real women do in real life.”

Based on the new data, Chappell’s recommendation would be for women with a fetus in the breech position to plan on having a Cesarean. But in some cases, women prefer a vaginal birth, so doctors and their patients have to have a conversation, she said. Counseling should include potential risks to the baby.

“I’ll use this data in my practice,” she said.

But doing a C-section on every mother with a breech baby is also not necessarily a sensible solution, since C-sections have costs and risks of their own, she said. Particularly for women who plan to have big families, having several C-sections may actually be more dangerous than a vaginal breech birth.

“You can make a recommendation to a pregnant woman, but she can take a different route,” Chappell said.

She would like to see more study of the specific counseling doctors give pregnant women to find out why 40 percent of women are still choosing a vaginal birth, and to see more successful “external cephalic versions,” which is the name of the technique for turning the baby head-down before birth.

It is important to reiterate that the vast majority of children born breech do well, Byrne said, but these results at least underscore that these types of births should be handled in the hospital.

A midwife could still be present, he said, but all the resources for dealing with a complication, or heading to an emergency C-section, should be close at hand.