Once a cesarean, always a cesarean?

by Daphne R. Howland

Once a cesarean always a cesarean? Undergoing a vaginal birth after a cesarean delivery (VBAC) is a difficult and sometimes controversial decision for pregnant women who have had a previous cesarean section.

Andrea had a difficult labor, an emergency cesarean section (C-section), and an agonizing recovery. Now she is determined not to have a baby by C-section this time—if she can help it. She feels strongly that her recovery was hampered by the surgery.

Every woman's experience of labor and delivery is unique. Cesarean childbirth, it turns out, is no different. In the 1970s, when the cesarean section rate tripled, the medical mantra was "once a cesarean, always a cesarean." These days, most women who have had at least one child delivered by C-section will have to decide whether to try to deliver a subsequent child vaginally. This is a decision colored by a complex set of factors, including:

  • A woman's own experience
  • The reason for the original C-section
  • Her subsequent recovery
  • Her overall health
  • Her personal preference
  • The opinion and philosophy of her physician

What makes the decision more complex is the fact that obstetrics professionals are struggling with the issue themselves.

Reducing the C-section rate through VBAC

Cesarean section—delivery of a fetus through the abdominal wall and uterus—is considered major surgery and accounts for some 25% of American childbirths. Blood loss is much greater than with vaginal delivery, and the risk of serious complications like hemorrhaging and infection are greater. Because it is not clear whether all these cesareans are necessary, the U.S. Department of Health and Human Services has set a goal to lower the rate to 15% by the year 2000.

Since repeat cesareans account for one-third of the cesarean rate, there is an effort underway to encourage women who have had a previous C-section to try to deliver vaginally whenever possible. Some managed care plans and insurers actually require a trial of labor, much to the consternation of obstetricians and many of their patients. In 1980 the VBAC rate was just above 3%; today it is more than 25%, according to the National Center for Health Statistics.

VBAC has risks, too

Although studies show that the vast majority—some 60% to 80%—of VBAC's are successful, enthusiasm for VBAC has recently been tempered. At the end of 1998, the American College of Obstetricians and Gynecologists (ACOG) published a practice bulletin strongly encouraging VBAC, but urging caution.

In their bulletin, ACOG warns that VBAC carries its own potential risks and financial costs, including the risk of uterine rupture. ACOG underscores that increasing the VBAC rate is not the only way to lower the cesarean rate, and stipulates that the decision be left to a woman and her physician.

"It is generally agreed that the current national cesarean delivery rate is high, so a lot of attention has been focused on reducing the repeat cesarean rate," says Stanley Zinberg, vice-president of ACOG practice activities. "While increasing the VBAC rate will help, the overall cesarean rate can be safely and effectively reduced by reviewing the indications for primary (first) cesarean, which accounts for the majority of the national rate."

Why a C-section?

The reason a woman had a cesarean in the first place often influences, or even dictates, her decision about a trial of labor for her next delivery. For example, women who undergo C-sections after long and difficult labors that didn't progress may face similar difficulties with subsequent deliveries. Statistically, however, women without any labor experience have more difficulties with VBAC than women who have labored before or after their cesarean.

The reasons for scheduled cesareans can include:

  • Baby in breech position. Though some physicians will allow women to deliver breech babies vaginally, the rate is low, especially for first-time mothers. A subsequent baby is unlikely to also be breech.
  • Placenta previa. The placenta blocks the cervix and is at risk of detaching before the baby is born; this condition is unlikely to repeat itself in a subsequent pregnancy.
  • Cephalopelvic disproportion. Baby's head is too large for the mother's pelvis. This is considered a controversial reason for C-section, because the proportion is difficult to measure and because small pelvises do often accommodate large babies during labor.
  • Fetal or maternal illness. This could make labor risky for mother and/or child.
  • Previous cesarean. The mother has delivered a previous child via C-section.

Reasons for unplanned or emergency cesareans include:

  • Labor that "fails to progress" (dystocia). Fetus is in distress despite prolonged active labor, or labor doesn't progress normally. This, too is controversial because fetal monitors can be misread and because "normal" is subjective.
  • Fetal distress
  • Infection in the mother

ACOG\s take on candidates for VBAC

Here's who ACOG thinks should try VBAC:

  • Most women who have had one or two cesareans with a low-transverse uterine incision, commonly referred to as the "bikini" incision. This incision allows muscle tissue to knit a scar that is much stronger than the older types of incisions, but it generally takes more time to perform, so physicians aren't always able to use this method in emergency situations.
  • Women with a pelvis large enough to accommodate the baby.
  • Women without any other uterine scars or ruptures, whether from previous cesareans or other surgeries.

ACOG also stipulates that whenever a woman is planning VBAC, a medical team should be on hand in case an emergency C-section is necessary. In some health care settings such as in some smaller hospitals or birth centers the lack of such a team would rule out any trial of labor for a VBAC.

A personal decision

A large part of the decision is up to the woman, and that means she must be well informed about VBAC.

"One thing today is patient choice. I think it's been misconstrued in recent years," says Bruce L. Flamm, MD, research chairman and professor of obstetrics at the University of California at Irvine and author of Birth After Cesarean: The Medical Facts. "The situation is going to be different for every woman. It depends very much on the woman and on her situation. The key thing is counseling."

As part of a California task force working to lower the cesarean rate, Dr. Flamm has worked hard to make sure women and physicians understand the risks of cesarean surgery. He strongly believes that the cesarean rate is too high. Still, he believes that an informed woman who chooses to have a repeat cesarean should absolutely have that option.

"VBAC is not risk-free, but women should also understand that elective repeat cesarean is not risk-free either," Dr. Flamm cautions. "The key issue is choice. Once she has all the information she needs, a woman should feel good about her choice. And she should be supported in what she wants."