Surgery

Vaginal Birth after Cesarean

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Vaginal Birth after Cesarean, Trial of Labor after Cesarean, VBAC, TOLAC

  • Contraindications
  1. Prior classic or T-shaped incision
  2. Prior transfundal uterine surgery
  3. Uterine scar other than low-transverse cesarean scar
  4. Contracted Pelvis
  5. Medical or obstetric complications preclude VBAC
  • Risk Factors
  1. Decreased success rate (associated with <60% successful VBAC)
    1. Two or more cesarean deliveries without a prior Vaginal Delivery
    2. Prior cesarean delivery for failure to descend in the second stage of labor
    3. Labor Induction needed
    4. Fetus >4000 grams
    5. Maternal Body Mass Index >40 kg/m2
    6. Maternal age over 35 years old
  2. Neutral success rate (associated with 65-75% successful VBAC)
    1. Gestational age >40 weeks
    2. Prior cesarean delivery for nonreassuring Fetal Heart Tones
    3. Prior cesarean delivery for Failure to Progress in the First Stage of Labor
    4. Unknown uterine scar type
    5. Twin Gestation
    6. Labor Augmentation
    7. Two prior cesarean deliveries with prior Vaginal Delivery
    8. Maternal Body Mass Index 25-40 kg/m2
  3. Increased success rate (associated with >75% successful VBAC)
    1. Prior successful Vaginal Birth
    2. Maternal BMI <25 kg/m2
    3. Prior cesarean delivery for Breech Presentation
    4. Spontaneous labor with Cervix determined to be ripe by Bishop Score
    5. Maternal age <35 years old
  4. References
    1. Leeman (2008) Obstet Gynecol Clin North Am 35(3): 473-95 +PMID:18760231 [PubMed]
  • Criteria
  • General (ACOG)
  1. One or two prior low-transverse Cesarean Sections
  2. Adequate Pelvis for delivery
  3. No contraindication (see above)
  4. Physician immediately available during active labor
    1. Capable of monitoring labor
    2. Immediate cesarean delivery available
  • Criteria
  • Low Risk (Northern New England VBAC Guideline)
  1. Conditions
    1. One prior low-transverse Cesarean Sections
    2. Spontaneous onset of labor
    3. No need of augmentation
    4. No repetitive Fetal Heart Rate abnormalities
    5. Prior successful Vaginal Birth after Cesarean delivery
  2. Management
    1. Provider responsible for cesarean delivery (backup) may have other acute care responsibilities
  • Criteria
  • Moderate Risk (Northern New England VBAC Guideline)
  1. Conditions
    1. Labor Induction
    2. Oxytocin augmentation
    3. Three or more prior low transverse cearean sections
    4. Last cesarean delivery was less than 18 months from the current delivery
  2. Management
    1. Provider responsible for cesarean delivery (backup)
      1. Must be present in the hospital during the Active Phase of Labor
      2. May have other in-hospital acute care responsibilities
    2. Operating room
      1. Open and staffed operating room available for emergency cesarean OR
      2. Other room available with adequate lighting where general anesthesia may be administered
    3. Anesthesia
      1. Anesthesia provider is in hospital during the Active Phase of Labor
      2. May have other in-hospital acute care responsibilities
      3. Established back-up protocol when anesthesia is busy with other responsibilities
  • Criteria
  • High Risk (Northern New England VBAC Guideline)
  1. Conditions
    1. Repetitive nonreassuring Fetal Heart Rate abnormalities refractory to interventions
    2. Vaginal Bleeding suggestive of Placental Abruption
    3. Labor Dystocia
      1. Two hours without cervical change in the active phase despite adequate labor
  2. Management
    1. Provider responsible for cesarean delivery (backup)
      1. Must be present in the hospital during the Active Phase of Labor
      2. May have NO other acute patient responsibilities
    2. Anesthesia
      1. Anesthesia provider is in hospital during the Active Phase of Labor
      2. May have NO other in-hospital acute care responsibilities
    3. Operating room
      1. Open and staffed operating room available for emergency cesarean
  • Precautions
  1. Cervical Ripening agents have higher risk of rupture
    1. Contraindicated in VBAC patients
  • Complications (VBAC considered to be relatively safe)
  1. Uterine Rupture (38 per 10,000 trials of labor)
    1. See Uterine Rupture for risks
  2. Perinatal death (1.4 per 10,000 trials of labor)
    1. Similar risk to Vaginal Delivery risk
    2. Contrast with 0.5 per 1000 births with elective repeat cesarean delivery
  3. Hysterectomy (3.4 per 10,000 trials of labor)
  4. References
    1. Guise (2004) BMJ 329:19-25 [PubMed]
  • Resources
  1. Northern New England VBAC Guidelines
    1. http://www.nnepqin.org/Guidelines.asp