Vaginal Birth After Cesarean SectionRisk to Patient, Provider and Public

Devon M. Fagel, J.D.OBGYN Clerkship

May 19, 2011

Learning Objectives• Understand the historic epidemiology of VBAC

• Identify both the medical risks and benefits of VBAC

• Explain the financial incentives for encouraging VBAC

• Describe the legal risks to physician and hospital facility

• Discuss the risks of overindulging patient autonomy

• Conclude with an example of VBAC complications

History & Epidemiology

• 1916: “Once a cesarean, always a cesarean”

• 1970: Rate of cesarean section at 5.5%

• 1978: Due to increase diagnosis of dystocia and concurrent rise in med-mal litigation, rate of C-sections dramatically increases

• 1980: NIH begins to encourage trial of labor (TOL) for VBAC.

• 1981: Rate of VBAC at 3.5%.

• 1988: Rate of C-section at 24.7%

• 1990: HHS proposes 15% goal for total C-sections which incorporated a 35% goal for VBAC.

Cochrane Database Syst Rev. 2004 Oct 18; (4)

Shifting Standards of Care

History & Epidemiology

• 1991: Rosen et al. found no significant difference in maternal mortality rate for elective repeat C-section (ERCS) vs. TOL.

• 1994: Flamm et al. reported TOL resulted in decreased rates of postpartum transfusions/fevers and shorter hospitalizations.

• 1997: Hook et al. reported infants born after TOL developed fewer neonatal respiratory problems compared with ERCS.

• 1990’s: Insurance companies and managed care organizations began to mandate that all women (except when contraindicated) must undergo a trial of labor.

• 1996: Rate of VBAC reached 28.3%, total C-section at 20.7%.

Cochrane Database Syst Rev. 2004 Oct 18; (4)

Shifting Standards of Care

History & Epidemiology

• 1999: NEJM editorial questioned safety of push for VBAC, reporting increasing rates of uterine rupture throughout 90’s.

• 1999: Several journals reported use of Misoprostol (which induces uterine contractions and ripening) resulted in 30-fold increase in uterine rupture compared to spontaneous labor.

• 2004: Cochrane review concluded, ERCS and VBAC are both “associated with benefits and harms.” Evidence drawn from non-randomized studies and thus present bias. “Any results must be interpreted with caution.”

• 2004: ACOG - “Because uterine rupture may be catastrophic, VBAC should be attempted in institutions equipped to respond to emergencies with physicians immediately available to provide care.

ACOG Practice Bulletin #54, July 2004

Shifting Standards of Care

• NIH admitted “general paucity of high-level evidence about both medical and non-medical factors, which prevents the precise quantification of risks and benefits that may help to make an informed decision about TOL vs ERCS.

• Panel’s “major goal to support pregnant women with one prior transverse uterine incision make an informed decision... and whenever possible, the woman’s preference should be honored.”

• Panel is “concerned about the barriers to clinicians and facilities that are able and willing to offer TOL... and recommends ACOG and ASG reassess requirement... for immediately available surgical and anesthesia personnel.”

• Panel is “concerned that medical-legal considerations exacerbate these barriers.”

NIH Consensus Statement, Volume 27, Number 3, March 8-10, 2010

Benefits of VBAC

• Lower rates of maternal morbidity including decreased postpartum fever, wound infection, blood transfusion, maternal discomfort, hysterectomy and length of stay

• Lower rates of neonatal respiratory distress

Risks of VBAC• Increased rates of uterine rupture (0.2% to 9% depending on

risks)

• Increased rates of perinatal death (.3% for ERCS vs .6% for TOL)

• Though inductions agents are generally contraindicated as studies have shown 5-30 fold increase in rates of uterine rupture, these agents continue to be used in VBACs.

• Additional risk factors include:• Maternal age > 30• Fetal weight > 4000g• No hx of vaginal delivery• Type of previous C-section

• Classical incision (4-9%)• T-shaped incision (4-9%)• Low vertical incision (1-7%)• Low transverse incision (0.2-1.5%)

The Problem with Patient Autonomy

• ACOG approved VBAC candidates

• Ability to perform emergency C-section

• No hx of previous uterine rupture

• Maximum of 2 previous CS

• Clinically adequate pelvis

• Vertex fetal presentation

• No other uterine scars

• Clinically adequate

The Problem with Patient Autonomy• Ability to perform emergency C-section

• Contraindicated with classical incision

• Maximum of 2 previous CS

The Problem with Patient Autonomy