VBAC Information
International Journal of Childbirth Education in November 1994 (Vol. 9, No. 4) Evidence confirming the safety of vaginal birth after cesarean (VBAC) within proper guidelines has been available for more than ten years. However, wide variations in VBAC rates, unjustified by medical factors, still exist between hospitals and physicians. These facts are presented with the hope that more women will be encouraged to avoiding unnecessary cesarean section and supported in their wish to labour and have a VBAC.
• VBAC with appropriate informed consent is the standard, of care for women with one prior low transverse uterine incision. Studies indicate that overall at least 50% and as many as 90% of women who plan a VBAC can delivery vaginally (ICEA VBAC Review 1990).
• The rate of reported uterine rupture in planned VBAC with a low transverse scar has ranged from 09% to .22%. This risk is thirty times lower than any other unpredictable childbirth emergency such as acute fetal distress, premature separation of the placenta and prolapsed umbilical cord. A 1994 study based on 5733 planned labours after one or more cesareans reported a rupture rate of .8% with no maternal deaths related to uterine rupture (Guide to Effective Care in Pregnancy and Childbirth 1992; Obstetric Gynecology 1994).
• Maternal morbidity rates are consistently and substantially lower for women who plan a VBAC - 2%-23% - than for women who have an elective repeat cesarean - 11%-38% (Guide to Effective Care in Pregnancy and Childbirth 1992).
• Any hospital that provides standard obstetric care can also provide care for women who wish to plan a VBAC. A recent study concluded that family physicians can play a major role in promoting VBAC (American Family Physician 1993).
• The National Association of Childbearing Centres of the United States (NACC) indicates that birth centres may encourage VBAC clients to tabor and deliver in their facilities provided that emergency care can be initiated within thirty minutes of recognition of a problem (NACC Committee Opinion 1989).
• In the United States, 22.6% of all births in 1992 were by cesarean section. Thirty-eight percent of all cesareans performed were elective repeat operations. The VBAC rate in 1991 was 24.2%. A national health objective for the year 2000 is a cesarean rate of 15% and a VBAC rate of 35% (Unnecessary Cesarean Sections: Curing a National Epidemic 1994).
• In 1988-89. the cesarean rate in Canada was 19.5%. Thirty-eight percent of all cesareans were repeat operations. The VBAC rate for this same period was 15.6%, a fivefold increase since 1979-80.Vaginal birth is safer for mothers in most cases. Numerous studies have conclusively shown that elective repeat cesarean is more hazardous for the woman, no safer for the baby, and poses serious risks to the woman's future reproductive life.
• The risk of uterine rupture associated with women who have had a previous cesarean with a low transverse incision are as follows: 0.16% (or 16 of every 10,000) with repeat elective cesarean, 0.54% (or 54 of every 10,000 women) with spontaneous onset of labor, 0.77% with inductions NOT involving prostaglandins (or 77 of every 10,000), and 2.45% with inductions involving prostaglandins (or 245 of every 10,000).
• In many reported series, true uterine rupture has not been distinguished from uterine scar dehiscence. Bloodless uterine scar dehiscence does not have negative consequences for mother or baby, whereas complete rupture of the uterus can be a life-threatening emergency. Fortunately the true rupture is rare in modern obstetrics, despite the increase in cesarean section rates.
Although often considered to be the most common cause of uterine rupture, previous cesarean section is a factor in less than half the reported cases.
• Prompt detection is crucial for timely management of uterine rupture. Clinical symptoms such as sudden tearing uterine pain, vaginal hemorrhage, cessation of uterine contractions, and regression of the fetus have proven to be unreliable and often absent. Fetal distress has been found to be the most reliable presenting clinical symptom.
• Maternal death is a rare complication of rupture, though it is more common in ruptures occurring outside of a hospital and in women with an unscarred uterus. Neonatal outcome after uterine rupture depend largely on the speed with which surgical rescue is carried out. In one study, best outcomes were noted when surgical delivery was accomplished within 17 minutes from the onset of fetal distress on electronic fetal heart rate monitors.
• If a hospital isn't safe for a VBAC labor, it isn't safe for any woman to labor there. Emergencies occur in non-VBAC labors, including uterine rupture, and there are other situations that increase the chances of needing an emergency cesarean where hospitals don't make special exceptions, such as induction of labor and epidural analgesia.
• It is a violation of the rights of the childbearing women to deny vaginal birth. The Informed Refusal statement issued by the American College of Obstetricians and Gynecologist in 2000 states, “Once a patient has been informed of the material risks and benefits involved with a treatment, test, or procedure, that patient has the right to exercise full autonomy in deciding whether to undergo the treatment, test, or procedure or whether to make a choice among a variety of treatments, tests, or procedures. In the exercise of that autonomy, the informed patient also has the right to refuse to undergo any of these treatments, tests, or procedures.
This information was prepared by ICAN of Colorado and collected from several reliable and well-respected sources, including the American Journal of Obstetrics and Gynecology and the New England Journal of Medicine