Caesarean section, resorted to unnecessarily many times, could be responsible for increasing trend of premature babies in the US. And that is a sign of worry.
For premature babies are at risk of breathing and feeding disorders, delayed brain development, other health problems and death.
A study of single births from 1996 to 2004 found an increase of one percentage point in premature deliveries, to 10.7 percent from 9.7. Ninety-two percent of those premature deliveries were by Caesarean. Most were "late preterm," born after 34 to 37 weeks of pregnancy, instead of the normal 38 to 42 weeks.
Late preterm babies make up more than 70 percent of all premature births in the United States, and are the fastest growing subgroup of preterm births, the researchers found. Even though they may seem close to full-term, they still face increased risks of serious problems from being born too early. The study focused on single births rather than multiple ones, because multiple births are much more likely to involve complications that require Caesareans, says Denise Grady, writing in New York Times.
The report was based on a review of birth records and previous studies, conducted by the March of Dimes Foundation, Albert Einstein College of Medicine and the federal Centers for Disease Control and Prevention. It is to be published in the June issue of Clinics in Perinatology, a medical journal.
The researchers say they cannot be sure how much prematurity can be blamed on unneeded Caesareans, because it is often hard to tell from medical records exactly why a Caesarean was done. The Caesarean rate has been climbing steadily in recent years, from 20.7 percent in 1996 to 30.3 percent in 2005.
"The practice of obstetrics has changed so dramatically in the past 20 years, so that induction of labor and Caesarean section have become the norm," said Dr. Alan R. Fleischman, the medical director and senior vice president of the March of Dimes.
But Dr. Sarah J. Kilpatrick, chairwoman of the department of obstetrics and gynecology at the University of Illinois, and chairwoman of the committee on obstetric practice for the American College of Obstetrics and Gynecology, took issue with some of Dr. Fleischman's comments and said there was no proof that unnecessary Caesareans were occurring or leading to premature births.
Noting that the college of obstetricians has guidelines stating strongly that labor should not be induced and Caesareans should not be performed before 39 weeks unless there is a genuine medical need for it, Dr. Kilpatrick said, "We stand by that."
She continued, "On the other hand, what I would agree with, I think there is pressure by patients on physicians to deliver early-ish when someone's uncomfortable, and there is medico-legal pressure. Obstetricians are afraid of being sued."
The fear of lawsuits is so great that at the first hint of a problem, Dr. Kilpatrick said, obstetricians "may proceed with a Caesarean to deliver the fetus when the fetus is probably fine."
She also said that obstetricians might have grown a bit complacent about delivering babies a few weeks early because pediatricians and neonatologists had become so good at taking care of premature infants.
"They may let their guard down around 36 weeks because they're so sure the baby will be fine," Dr. Kilpatrick said. "This paper is a good reminder to everybody that 36 weeks is still preterm.