TOLAC

Question 1

Describe uterine dehiscence and uterine rupture

Answer 1

• Uterine dehiscence - occult scar separation. Serosa of the uterus is intact → no hemorrhage
• Uterine rupture - through-and-through disruption of all uterine layers→ potential consequences of nonreassuring fetal status and perinatal mortality along with severe maternal morbidity, hemorrhage, and mortality. HIE.
  
  • Rate depends on previous incision
    
    • Low transverse - 0.5 - 1%
    • Classic or T-shaped - 4 - 9%
  • Other risk factors:
    
    • # of prior C/S and vaginal deliveries
      • Vag delivery protective against rupture regardless of when it was
      • More C/S → higher risk (only slightly higher from 1 → 2)
    • Interdelivery interval
      
      • < 18-24 month → higher risk
    • Uterine closure technique
      
      • single layer closure may be associated with increased risk (but other factors make it hard to tell)
    • Induction of labor
      
      • mixed evidence. Cervical ripening prostaglandins appear to increase risk.
    • Augmentation of labor
      
      • Pitocin at higher doses increases risk (1.5%)

Question 2

Describe the use of sonography in screening for these complications

Answer 2

Basically there is no use to it.

No cutoff values have been found so far in using US to measure:

• Thickness of residual myometrium in the LUS
• Width, depth, and length of the hypoechoic interface at the site of the prior cesarean delivery

Measurements may change with GA

Question 3

RISKS ASSOCIATED WITH TRIAL OF LABOR AFTER CESAREAN DELIVERY

Answer 3

• Uterine Rupture and Related Morbidity
  
  • Uterine rupture (0.5-1.0/100)
  • Perinatal death and/or encephalopathy (0.5/1000)
  • Hysterectomy (0.3/1000)
• Increased Maternal Morbidity With Failed TOLAC
  
  • Transfusion
  • Endometritis
  • Length of stay
• Other Risks With TOLAC
  
  • Potential risk for perinatal asphyxia with labor (cord prolapse, abruption)
  • Potential risk for antepartum stillbirth beyond 39 weeks’ gestation

Question 4

Risks associated with a planned repeat C/S

Answer 4

• Increased maternal morbidity compared with successful trial of labor
• Increased length of stay and recovery
• Increased risks for abnormal placentation and hemorrhage with successive C/S deliveries

Question 5

Attributable outcome risk of perinatal mortality or HIE

Answer 5

1 in 2,000 TOLACs

Question 6

When does most maternal morbidity happen with TOLAC?

Answer 6

When a C/S becomes necessary

(i.e “failed” TOLAC)

Question 7

You have a patient with hx of C/S in another country with no op report available. Can they attempt TOLAC?

Answer 7

Yes.

Question 8

VBAC “success” rate

Answer 8

60 - 80%

Depends on the circumstances of the prior C/Ss and hospital policies, etc.

Question 9

Risk factors for “unsuccessful” VBAC

Answer 9

• Increasing maternal age
• High BMI
• High birth weight
• GA > than 40 weeks at delivery
• Shorter interdelivery interval (< than 19 months)
• PEC

Question 10

True or false:

Patients with at least a 60–70% likelihood of achieving a VBAC who attempt TOLAC experience the same or less maternal morbidity than patients who have an elective repeat C/S

Answer 10

True

Question 11

6 steps of shared decision making

Answer 11

1. Invite patient to participate
2. Present options
3. Provide information on benefits and risk
4. Assist patient in evaluating options based on their goals and concerns
5. Facilitate deliberation and decision making
6. Assist with implementation

Question 12

Recurring vs non-recurring indications for C/S

Answer 12

Recurring:

• arrest of labor
• arrest of decent
• previous uterine surgery
• possibly HSV
• CPD

Non-recurring

• Malposition
• previa
• cord prolapse
• elective

Question 13

Contraindications to TOLAC

Answer 13

• Previous classical or T-incision
• Extensive transfundal uterine surgery
• Prior uterine rupture
• Medical or obstetric complications that prohibit vaginal birth
• NOTE: suspected macrosomia is NOT a contraindication

Question 14

Candidates to TOLAC

Answer 14

• One or two previous low transverse C/S’s
• Clinically adequate pelvis
• No other uterine scars or previous rupture
• Physicians immediately available throughout active labor capable of monitoring labor and performing an emergency C/S

Question 15

Mutualism, or shared, decision-making

Answer 15

Assumes that:

• the provider informs the woman of all relevant information
• the woman informs the provider of her medical history as well as her values, preferences, lifestyle, beliefs, and knowledge
• the provider individualizes his or her approach to consider the needs and value system of the woman
• the provider and the woman interact and engage in a process to arrive at a consensus
• both parties have an equal investment in the decision