Study Links Caesareans With Births Before Term
By DENISE GRADY
Published: May 28, 2008
Premature single births have been increasing in the United States, mostly among infants delivered by Caesarean section, researchers are reporting. And they say some of the increase may be due to Caesareans that are not medically necessary.
The trend is worrisome because premature babies are at risk for 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.
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.
In observations at community hospitals across the country, researchers have seen obstetricians stretching diagnoses a bit to justify Caesareans that are not truly necessary, Dr. Fleischman said.
“Perhaps for convenience, perhaps out of fear of litigation, perhaps in response to a maternal request, they are scheduling their deliveries rather than allowing labor to begin,” he said. “And this comes when there is an epidemic in America of prematurity.”
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.”
C-Sections Increasing U.S. Premature Births: Study
Some Doctors Concerned Elective Procedures Put Babies at Unnecessary Risk
By Will Dunham
May 28, 2008
Clara Elaine Tuley, born Jan. 4, 2008, was 1-pound 6-ounces when she was delivered by emergency... Expand
Clara Elaine Tuley, born Jan. 4, 2008, was 1-pound 6-ounces when she was delivered by emergency Caesarean section, to Jolene Tuley, right, who was 23 1/2 weeks into her pregnancy. Clara, shown in her crib at Vanderbuilt Children's Hospital, in Nashville, Tenn., Tuesday, April 15, 2008, is now 5-pounds 5-ounces and is scheduled to go home to Mount Juliet, Tenn., soon. Collapse
(Bill Waugh/AP Photo)
WASHINGTON (Reuters) - Premature births of U.S. babies have been climbing since the mid-1990s and the increase is being driven by Caesarean section deliveries, according to a study published on Wednesday.
Dr. Alan Fleischman, medical director and senior vice president of the March of Dimes infant health advocacy group, voiced concern that a sizable portion of these C-section deliveries may be medically unnecessary.
Premature babies are at greater risk for a number of medical and developmental problems such as troubled breathing, bleeding in the brain, birth defects and death. Premature birth is defined as delivery before the 37th week of pregnancy, rather than the typical 40 weeks.
Researchers at the U.S. Centers for Disease Control and Prevention and the March of Dimes compared single births -- not twins or other multiple births, which are at an increased risk for pre-term birth -- in 1996 and 2004. The rate of premature births rose by about 10 percent in that period, they said.
The number of premature births rose from 354,997 in 1996 to 414,054 in 2004, the study published in the journal Clinics in Perinatology showed.
"When one looks at the numbers carefully, there was an increase of 60,000 who were pre-term, and 92 percent of them were by Caesarean section," Fleischman said.
The increase comes amid an ongoing controversy over whether some doctors are performing C-sections because they fear being sued if they do not and whether some women are opting for medically unnecessary C-sections out of convenience.
A C-section -- delivery of a baby through a surgical abdominal incision -- is advised when a vaginal birth is not possible or is unsafe for the mother or child.
"The increase in pre-term births is really being driven by the Caesarean section rate, and really demands good research to sort out what percent of those are not medically indicated deliveries," Fleischman said in a telephone interview.
"My gut tells me its significant, but I can't give you an estimate and a percent," Fleischman added.
There has been considerable controversy in the medical field over a dramatic increase in C-section births in the United States and some other countries in recent decades.
In the United States, 5 percent of babies in 1970 were born by C-section. In 2006, the figure was about 31 percent.
Meanwhile, the percentage of babies born prematurely also has been rising -- increasing more than 30 percent since the early 1980s to about 13 percent of all births. Being born pre-term gives an infant less time to develop in the womb.
(Editing by Anthony Boadle)
Copyright 2008 Reuters News Service. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
Clinics in Perinatology
Volume 35, Issue 2, Pages 293-468 (June 2008)
Cesarean Delivery: Its Impact on the Mother and Newborn-Part I
Edited by Lucky Jain, Ronald Wapner
Lucky Jain, Ronald Wapner
How will our grandchildren be delivered?
Who would have thought that we would be asking this question in the year 2008? Yet the current debate on the pros and cons of vaginal and cesarean births is more vociferous than ever, spurred, in particular, by the rapid rise in cesarean births. Rising from a mere 5% of total births in the United States in 1970, this year nearly one out of every three births in the United States will occur by operative delivery. The rate of rise is even more spectacular in some other countries. The highly publicized decisions by celebrities to have cesarean births and the lay information related to pelvic floor dysfunction, among other things, may be encouraging some mothers to recommend their own mode of delivery. This decade will go down in history as the decade when “cesarean delivery on maternal request” became an official term!
One wonders, though, why there is all this fuss over an aspect of human life that has coexisted in harmony with the medical profession for hundreds of years. There is evidence to show that cesarean births have improved the outcome in several high-risk categories, such as breech presentation, very early gestations, and in cases where there is evidence of fetal distress. However, new concerns have emerged about the short- and long-term risks and benefits of either mode of delivery. The absence of clear evidence to show that one is better than the other has led to a conundrum. As would be expected, maternal benefits are sometimes at odds with neonatal interests. There is fascinating anthropological information that shows the progressively increasing brain volume (eg, skull size) of the human fetus at birth, coupled with the concomitant changes in the pelvic anatomy as a result of bipedalism, may have set up a natural conflict for spontaneous vaginal birth for future generations.
So how do we resolve this issue and provide an evidence-based recommendation to families seeking counsel for one of the most important decisions of their reproductive lives? Some have suggested that a randomized head-to-head trial of low-risk or no-risk mothers comparing cesarean to vaginal birth is essential―perhaps the only definitive way to answer this question. However, cost and logistical issues notwithstanding, it is not clear how such a study could be pulled off, given the huge number of participants it would need and the ethical debate it would be certain to stir.
One good outcome of all this is the much needed attention this subject is finally receiving. This first-ever issue of the Clinics in Perinatology devoted to cesarean delivery is an example of that. We are particularly delighted to spearhead this two-issue offering of Clinics in Perinatology dedicated entirely to cesarean birth. The first issue focuses on the epidemiology and neonatal outcomes after cesarean section. The second issue, due to be published later this year, will focus on maternal topics. We are very grateful to Carla Holloway at Elsevier for her unwavering support, and to all of our colleagues who have contributed to this project.
We hope this compilation of articles by experts in the field will serve as a handy reference for a variety of topics related to cesarean birth. Meanwhile, the search for the ideal mode of delivery for the next generation and the next will continue!
Department of Pediatrics, Emory University School of Medicine, 2015 Uppergate Drive NE, Atlanta, GA 30322, USA
Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Columbia University School of Medicine, New York, NY 10021, USA
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