A Randomized Trial of Induction Versus Expectant Management
- Parkland Health & Hospital System
Brian Casey, M.D.
Induction in Nulliparous Women at 39 Weeks to Prevent Adverse Outcomes: A Randomized Controlled Trial
A randomized clinical trial to assess whether elective induction of labor at 39 weeks of gestation compared with expectant management will improve outcomes.
Given the reported increased risks of adverse events in pregnancies extending beyond 39 weeks it has been hypothesized that a policy of planned elective induction at 39 weeks could improve outcomes for the infant and the mother. For multiparous patients, especially those with a favorable cervix, it is perhaps easy to justify an elective induction at 39 weeks given the low risk of cesarean section. However, for nulliparous patients the current evidence, derived mainly from retrospective observational studies, does not allow a clear recommendation. Nevertheless, a trend towards an increased rate of elective labor induction in pregnancies at 39 weeks has been reported, indicating that practitioners are more commonly using elective induction at this gestational age,even as others caution against routine elective induction prior to 41 weeks given the reported increased risk of cesarean delivery. Ultimately, a randomized controlled trial is necessary to satisfactorily understand whether elective induction of labor of nulliparas at 39 weeks improves neonatal and maternal outcomes.
1. Nulliparous - no previous pregnancy beyond 20 weeks
2. Singleton gestation. Twin gestation reduced to singleton, either spontaneously or therapeutically, is not eligible unless the reduction occurred before 14 weeks project gestational age.
3. Gestational age at randomization between 38 weeks 0 days and 38 weeks 6 days inclusive based on clinical information and evaluation of the earliest ultrasound.
1. Project gestational age at date of first ultrasound is > 20 weeks 6 days
2. Plan for induction of labor prior to 40 weeks 5 days
3. Plan for cesarean delivery or contraindication to labor
4. Breech presentation
5. Signs of labor (regular painful contractions with cervical change)
6. Fetal demise or known major fetal anomaly
7. Heparin or low-molecular weight heparin during the current pregnancy
8. Placenta previa, accreta, vasa previa
9. Active vaginal bleeding greater than bloody show
10. Ruptured membranes
11. Cerclage in current pregnancy
12. Known oligohydramnios, defined as AFI < 5 or MVP < 2
13. Fetal growth restriction, defined as EFW < 10th percentile
14. Known HIV positivity because of modified delivery plan
15. Major maternal medical illness associated with increased risk for adverse pregnancy outcome (for example, any diabetes mellitus, lupus, any hypertensive disorder, cardiac disease, renal insufficiency)
16. Refusal of blood products
17. Participation in another interventional study that influences management of labor at delivery or perinatal morbidity or mortality
18. Delivery planned elsewhere at a non-Network site