March 19, 2005
Once a Caesarean Always a Caesarean?
Doctors reexamine the question of vaginal birth after a c-section
HealthDay News -- Having a baby is always full of fateful decisions. One is whether to have an elective Caesarean section. Even more debatable is the decision to have a vaginal birth after having had a Caesarean for the previous baby.
A generation ago, there was little or no debate. Women rarely chose a Caesarean but had one only if necessary, usually a life-saving alternative. From that point on, the mantra among obstetricians was once a Caesarean always a Caesarean. Anything else was generally deemed much too risky.
But then two things happened. First, the rate of Caesareans climbed sharply, from 5 percent in 1970 to 26 percent in 2002, often for the convenience of the mother or for the schedule of the obstetrician. A recent study in the British Medical Journal found that first-time Caesareans in women with no apparent medical need -- a so-called elective Caesarean -- rose by 67 percent in the United States, from 3.3 percent to 5.5 percent overall, from 1991 to 2001.
Meanwhile, obstetricians realized that vaginal birth after Caesarean (VBAC) wasn't so risky after all, and it was at least worth a try for most women. So VBAC, a new acronym, entered the medical lexicon, along with the ubiquitous c-section.
In the 1990s, VBAC became the way to go for large numbers of women. About 31 percent elected trial by labor in deliveries after a c-section in 1998, up from 3 percent in 1981. VBAC became nearly as trendy for mother and child as breast-feeding.
Then, two more things happened. Malpractice suits began to send insurance premiums soaring for obstetricians who had joined the VBAC parade for their patients. And then studies suggested that while VBAC was much less risky than doctors used to believe, it was not without risk.
By 2002 these factors had an impact. The VBAC rate fell to 12.6 percent in 2002. Many doctors stopped doing VBAC because of liability fears. A survey by the American College of Obstetricians and Gynecologists (ACOG) revealed that 14.8 percent of its members no longer offered VBAC.
At the same time, ACOG issued a statement on the ethics of how doctors can advise women to have elective Caesareans in the absence of solid safety data.
The most recent big study, published in December in the New England Journal of Medicine, reported that 587 of 588 women will do just fine in a trial by labor after a previous VBAC. But that 1-in-588th delivery could have serious problems for mother or child, mostly uterine ruptures, despite special precautions that are taken for a VBAC delivery.
Of the women who underwent trial of labor, 0.7 percent had uterine rupture, while 12 infants had brain damage from lack of oxygen, seven of them following uterine rupture; two babies died. This translates into an absolute risk of 0.46 per 1,000 women.
"For women undergoing trial of labor, the overall risk of one of these serious adverse outcomes at term is one in 2,000 trials of labor," said study chairman Dr. Mark B. Landon, of Ohio State University. "For many women, that level of risk is clearly acceptable, with the benefit being a potential vaginal birth with shorter recovery, less hospitalization, and the satisfaction that goes with vaginal delivery itself. For other women, any level of potentially preventable fetal risk is unacceptable."
On the other hand, the study did not assess the potential risks of repeat c-sections.
Authorities at a meeting in New York City, sponsored by the Maternity Center Association, reported that women who have an elective c-section are at a significantly higher risk of pain after surgery, infection, re-hospitalization and problems with subsequent pregnancies. In short, an elective Caesarean is not necessarily innocuous, equal to a first-time vaginal birth.
Babies delivered by c-section are less likely to be breast-fed, seem to have a higher risk for asthma, and, if born before the 39th week of pregnancy, are more likely to have respiratory problems than babies delivered vaginally, according to the speakers.
"Choosing whether to have a vaginal delivery or an elective Caesarean section is based on the premise that these two choices are essentially equivalent, but this is simply not true," said Eugene Declercq, one of the panelists and a professor of maternal and child health at the Boston University School of Public Health.
As to VBAC, a government study noted that "patients, clinicians, insurers and policymakers do not have the data they need to make truly informed decisions about appropriate delivery choices following one of the most common surgical procedures performed on women."
The National Institutes of Health has a brief history of the Caesarean section.