Labor Induction


- Indicated when prolonging the pregnancy puts the mother, the fetus, or both at risk.
- The most common indication is for post-term pregnancy (≥ 42 weeks); however, induction may be necessary at any gestational age.
- If possible, fetal lung maturity should be established either by accurate pregnancy dating (OB US @ , 20wk) or by amniocentesis, and if necessary, corticosteroids should be administered for fetal lung maturity.

    When do i induce labor in a term pt.?
    - OB US @ < 20 wk gestation confirming term pregnancy (>39 wks)
    - Vertex position

The method of induction depends on the extent of cervical ripening as assessed by the Bishop score. Once determined, Bishop scores are interpreted as follows:
 

Score

CERVIX 0 1 2 3
Position Posterior Midposition Anterior -
Consistency Firm Medium Soft -
Effacement 0-30 40-50 60-70 ≥ 80
Dilation Closed 1-2 3-4 ≥ 5
Station −3 −2 −1, 0 +1, +2