WASHINGTON, D.C. - It may not be immediately apparent in your local maternity ward, but the nation's medical establishment is giving some not-too-subtle encouragement for obstetricians and moms to deliver more babies without cesarean section surgery -- currently the method by which nearly a third of infants arrive.
Maternal America hit several modest milestones for births by cesarean section in the past few years.
After going up for a decade, the C-section rate held steady at 32.9 percent in 2008 and 2009, then dipped to 32.8 percent in 2010 and stayed there in 2011, the latest year figures from the Centers for Disease Control and Prevention are available.
That's notable because the cesarean rate increased from one in five births in 1996 to one-in-three by 2007.
The increases occurred among women of all age groups and ethnic backgrounds, rising to nearly half of births by women in their 40s and older.
What's troubling, though, is that rates for the most common surgical procedure in America vary widely from state to state, from as low as 25 percent in Alaska and several western states to more than 35 percent in Florida, Louisiana, Mississippi, New Jersey and West Virginia.
The variation is even greater from hospital to hospital.
An analysis of nearly 600 hospitals that performed at least 100 live births in 2009 found C-section rates as low as 7 percent and as high as 70 percent, according to a study published earlier this month in the journal Health Affairs. Even among women with lower-risk pregnancies, the rates ranged from 2.4 to 36.5 percent.
The numbers suggest that something other than medical necessity or the types of patients are driving the differences, researchers from the University of Minnesota said. The styles of practice of individual doctors or physician groups in one hospital make a difference.
That's not to say that medical need doesn't play a big role.
Researchers at Yale reported last year on 30,000 births at Yale-New Haven Hospital between 2003 and 2009.
They found that traditional, objective reasons for C-sections -- such as babies in difficult breech positions or complications with the placenta -- have remained steady. But reports of more subjective problems, like slow progression of labor or concerns about fetal heart rate have been increasing, along with a trend to use the procedure more often with larger infants and twins.
The Yale study found that maternal choice or scheduled C-sections were responsible for only about 8 percent of the increase in procedures at the hospital. However, a small Swedish study published last year noted that women with a fear of childbirth were nearly twice as likely to have a C-section as those with no such fears, even after special counseling.
More than 90 percent of women who've had a C-section will repeat the procedure if they give birth again, and those deliveries account for about a third of the total each year. Many hospitals discourage attempting labor with subsequent births due to fears of complications, although this is changing in some areas.
Convenience, pain and risks to mom and baby aside, there are also strong arguments to encourage vaginal births, not the least of which is that C-sections typically cost about twice as much as a standard delivery.
More and more evidence indicates that natural delivery benefits infants in areas ranging from immune system development and reduced odds for asthma and allergies to early growth patterns.
There's particular concern that elective C-sections contribute to more preterm births. Although a full term pregnancy is considered 37 to 41 weeks, most experts recommend waiting until at least 39 weeks for delivery.
Medicaid has launched an initiative with several hundred hospitals to discourage early elective deliveries. The American College of Obstetricians and Gynecologists recommends against early deliveries by any method before 39 weeks without sound medical need.
A study by Johns Hopkins researchers presented last year showed that C-section delivery may not protect babies who are small for their gestational age, but in fact may give them higher odds for breathing problems.
Starting next year, the Joint Commission -- the national accrediting organization for healthcare organizations -- will require hospitals with more than 1,100 births a year to actively work toward reducing C-sections among first-time moms at low risk for complications and decreasing early elective birth rates.
While there are no benchmarks or quotas, the new measure pressures hospitals to monitor and evaluate their C-section rates and consider changes in their standard practices.
(Contact Scripps health and science writer Lee Bowman at BowmanL@shns.com.)