Hospital itself is greatest risk factor in C-section birth, Consumer Reports investigation says

While there are a number of risks that can make birth by cesarean section more likely for women, a Consumer Reports investigation said the biggest risk factor is the hospital where the mother delivers, and how busy they are.

The investigation examined operations at more than 1,300 hospitals nationwide. Not only did it suggest that hospitals were the biggest risk factor, its results showed that C-section rates for low-risk deliveries vary tremendously, even between hospitals located in the same or nearby communities.

C-sections are the most common major surgery performed in the U.S., with one out of every three babies delivered this way, according to a recent study from the journal Birth cited by Consumer Reports. Though some c-sections are medically necessary, researchers have estimated that nearly half of C-sections done in the U.S. aren't.

The CR investigation focused on first-time mothers-to-be who should have been at low risk for c-section, meaning moms who are expecting just one baby that is full-term and positioned head first. The most recent available average C-section rate for those births was 25.8 percent, which is almost two full percentage points above the target rate set by the Department of Health and Human Services.

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"Once cesarean rates get well above the 20s and into the 30s, there's probably a lot of non–medically indicated cesareans being done, That's not good medicine," says Aaron B. Caughey, M.D., chair of the Department of Obstetrics and Gynecology at Oregon Health & Science University School of Medicine in Portland.

Nevertheless, CR said six in 10 hospitals they looked at had C-section rates above that national target for low-risk births. Rates of risk for having a c-section varied depending on where women lived, and were generally higher in the Northeast and South, and lower in the West and Midwest.

Four states in particular had rates at or above 30 percent: West Virginia at 31 percent, Florida at 31 percent, Louisiana at 32 percent and Nebraska at 34 percent.

Conversely, four states had admirably low rates below 18.5 percent: South Dakota at 17 percent; Idaho at 17 percent; New Mexico at 17 percent and Minnesota at 18 percent.

[Also: Half of states report 50 percent or more of births financed by Medicaid]

"The differences between C-section rates among individual hospitals for first-time, low-risk deliveries is even more dramatic than at the state level. For large hospitals, they ranged from 7 percent at Crouse Hospital in Syracuse, N.Y., to 51 percent at South Miami Hospital in Miami," Consumer Reports said.

One hospital just outside of Miami, Hialeah Hospital, showed a low-risk cesarean birth rate of 64.6 percent. A spokesperson said they are focused on providing appropriate services to patients based on their needs, and examine their delivery data for practice patterns. Their C-section rate remained the highest in the country of all hospitals in CR's ratings.

There are a few factors contributing to the high rate of c-section births in low-risk pregnancies. First, the use of continuous fetal heart rate monitoring can create anxiety about non-emergencies. While the technology was implemented in the 1970s to decrease newborn deaths, the only thing they do in low-risk births is drive up the C-section rates, according to Neel Shah, MD, an assistant professor of obstetrics, gynecology, and reproductive biology at Harvard Medical School, who has studied C-section rates in the U.S. and abroad. He said the monitors only identify a real problem about 15 percent of the time, often causing overreaction on the part of physicians.

[Also: Wide price variations in cost of childbirth highlight inefficiency of healthcare market]

Another cause is known as prolonged labor. Physicians may intervene when they think labor is moving too slowly based on the notion that longer labors lead to complications, said Amy Romano, a certified nurse midwife and senior vice president of clinical programs for Baby+Company, who contributed to the report. However the standards on how long labor should take are based on information from the 1950s, Romano said.

Finally, depending on when a women comes into the hospital and how busy the hospital is, that can propel some doctors to rush a birth to free up beds. Also, because hospitals frequently have less staff working on holidays and weekends, that also increases the likelihood of cesarean birth, the CR report said.

According to a study in the journal Birth cited in the CR report, more than half of women would travel 20 miles farther to deliver in a hospital with a c-section rate that was 20 points lower, however ultimately lowering c-section birth rates is up to hospitals and doctors, the report said.

And it is an effort well worth making. Shah pointed out that C-sections are major surgery, and therefore carry the risks of any hospital procedure. "Unnecessary C-sections may be responsible for up to 20,000 major surgical complications a year, including everything from sepsis to hemorrhage to organ injury."

Women with low-risk pregnancies who have their first C-section were three times more likely to die, or suffer serious complications like blood clots, heart attack, and major infections, compared with women delivering vaginally. That's according to a 14-year analysis of more than 2 million women in Canada published in 2007 and cited by American Congress of Obstetricians and Gynecologists guidelines, the CR report said.

Still another reason to avoid an unnecessary c-section is that it greatly increases a mother's probability of having to deliver future children in the same way, as much as a 90 percent likelihood. It also takes women longer to recover from a c-section birth and a vaginal birth has been professed to be better for the infant. "They are less likely to suffer breathing problems and more likely to be breastfed, perhaps because it's easier to get breastfeeding going when mothers are not recovering from major surgery," the report said.

Finally, C-section births carry greater expense. CR cited figures that said the average cost for a C-section in the U.S. today is $16,038, compared with $12,560 for a vaginal birth. That can vary by as much as $10,000 across the country.

Twitter: @BethJSanborn