Women who attempt normal deliveries after previous Caesarean sections run a very low risk of uterine tears and other complications, doctors leading a nationwide study said yesterday.
The risk is slightly higher than it is among women who have repeat Caesareans - but not enough to justify denying women the option of vaginal deliveries or scaring them away from trying, researchers said.
Dr. Mark B. Landon, an obstetrician with Ohio State University Medical Center and the study's principal investigator, said exaggerated claims about the dangers have led to a steep decline in the number of vaginal births after Caesareans, also known as VBACs.
Last year, 10 percent of pregnant women who had prior Caesareans attempted to deliver vaginally - down from 30 percent in 1996. Some doctors have refused to assist women in VBACs, and some hospitals, particularly in rural areas, have adopted policies forbidding them.
"I think the risk has been inflated by some, and it may in fact be concealed in the counseling process in an effort to steer certain women to having repeat operations," Landon said.
"The message is that this option should remain there for women and that meaningful counseling should be undertaken for women who are considering the option of VBAC."
The decline in VBACS has been partly responsible for a continued rise in the nation's Caesarean section rate, which last year rose to its highest level ever. Despite staunch efforts in the 1990s to lower the C-section rate, more than 27 percent of the 4 million babies born in America last year were born surgically.
In the study, appearing in this week's New England Journal of Medicine, doctors at 19 medical centers compared outcomes of 17,898 women who attempted VBACS and 15,801 who had repeat Caesareans. None of the women had a medical reason for her C-section, such as a breech baby or signs of fetal distress.
Among the women attempting vaginal deliveries, 0.7 percent - or 124 women - had uterine ruptures, compared with none among the C-section patients. Using the drug oxytocin to induce labor among those with vaginal deliveries increased the risk to 1.1 percent. But there were no ruptures among women receiving another class of drugs, called prostaglandins.
Twelve babies born through the birth canal were diagnosed with a condition called hypoxic ischemic encephalopathy, in which the brain is deprived of oxygen. Seven of those apparently resulted from uterine ruptures. Two babies died.
When such ruptures occur, the uterus typically tears along the scar from the previous Caesarean.
For some doctors, even the remote chance of a rupture is sufficient reason to withhold offering a VBAC.
"If you are that one person out of a hundred, it's you - it's 100 percent you, your child or your uterus," said Dr. Gerrit Schipper, chief of obstetrics at Frederick Memorial Hospital. "And it's a week and a half in the intensive care unit and a blood transfusion."
In August, the hospital decided it would no longer allow patients to attempt vaginal births after Caesareans - a decision that later drew an angry protest outside the hospital by 50 women and their children.
Schipper said many hospitals, including Frederick, can no longer accept the chance of being sued if a VBAC goes wrong. Lawsuits waged by parents of brain-damaged babies generate some of the highest awards and settlements in the malpractice arena.
"The reality of the American legal system looms in the background," Schipper said. "As a society, we are not accepting bad outcomes. Even if a woman consents and agrees [to a VBAC], since they are the one with the problem, all of that becomes baloney. All of that comes back to you."
Barbara Stratton, who leads the Baltimore chapter of the International Cesarean Awareness Network, said the study supports her view that VBACs are a safe option.
"I'm happy with this study as a mom who is going to be a VBAC'er herself if I become pregnant again," said Stratton, who said her 1999 Caesarean left her in pain for 1 1/2 years and suffering from postpartum depression. "Do I believe that the safest choice is to go on and have a vaginal birth? Absolutely I do."
Dr. Catherine Spong, chief of the pregnancy and perinatology branch of the National Institute of Child Health and Human Development, said that the small risk of uterine rupture with VBAC should be weighed against the long-term risks associated with repeat Caesareans.
With each repeat operation, she said, a woman has a greater chance that the placenta will grow into the uterus or attach to the cervix. These complications can cause ruptures, bleeding and the need for an emergency hysterectomy, she said.