brand logo

This is a corrected version of the article that appeared in print.

Am Fam Physician. 2022;105(2):177-186

This clinical content conforms to AAFP criteria for CME.

Author disclosure: No relevant financial relationships.

Induction of labor is a common obstetric procedure, and approximately one-fourth of pregnant patients undergo the procedure. Although exercise and nipple stimulation can increase the likelihood of spontaneous labor, sexual intercourse may not be effective. Acupuncture has been used for labor induction; however, it has not been shown to increase vaginal delivery rates. There is strong evidence that membrane sweeping can increase the likelihood of spontaneous labor within 48 hours. Cervical preparation or ripening is often needed before induction. Some evidence shows that the use of nonpharmacologic approaches such as osmotic dilators and cervical ripening balloons reduce time to delivery. The effect of amniotomy on labor is uncertain. Pharmacologic intervention with oxytocin or prostaglandins is effective for cervical ripening and induction of labor. Combining a balloon catheter with misoprostol is a common practice and has been shown to decrease time to delivery in a small study.

Induction of labor is one of the most common obstetric procedures and is performed for approximately one-fourth of pregnancies.13 Induction involves establishing cervical favorability, also called cervical ripening, and stimulating contractions to induce active labor.

RecommendationSponsoring organization
Do not schedule non–medically indicated (elective) inductions of labor or cesarean deliveries before 39 weeks 0 days gestational age.American Academy of Family Physicians
American College of Obstetricians and Gynecologists

Indications for Induction

Induction of labor is indicated when the risks of continuing the pregnancy outweigh the risks of induction, with the goal of delivery while minimizing risks to the mother and newborn. Maternal, fetal, and placental conditions can increase the risk of continuing a pregnancy. Common medical indications for induction of labor and recommended timing are covered in Table 1 [corrected].4

IndicationSuggested timing (weeks' gestation)

EarliestBefore
Maternal
Chronic hypertension
 No medications3840
 Well controlled3740
 Poorly controlled or proteinuria3638
Gestational hypertension37At diagnosis if later than 37
Preeclampsia
 No severe features37At diagnosis if later than 37
 Severe features (immediate if unstable)34At diagnosis if later than 34
Prepregnancy diabetes mellitus
 Well controlled3940
 Well controlled but vascular disease3639
 Poorly controlled3639
Gestational diabetes
 Well controlled with diet (A1)3941
 Well controlled with medication (A2)3940
 Poorly controlledIndividualized
Cholestasis of pregnancy3639
HIV infection (if viral load ≤ 1,000 copies per mL)39
Fetal
Fetal growth restriction
 Single gestation, no issues3839
 Single gestation, other conditions3438
 Twin gestation, no issues3638
 Twin gestation, monochorionic or other condition3235
Oligohydramnios3638
Polyhydramnios3941
Alloimmunization3739
Multiple gestation
Dichorionic diamniotic3839
Monochorionic diamniotic3438
Monochorionic monoamniotic3234
Obstetric
History of stillbirthIndividualized
Late term4142
Note: The placental disorders placenta previa, vasa previa, and invasive placental disorders were removed from this table because all typically require cesarean delivery.

Induction of labor before 39 weeks' gestation increases neonatal morbidity and mortality and is not recommended without a medical indication.5,6 Several studies demonstrate that induction of labor at 41 weeks leads to similar outcomes as induction at 42 weeks. Pregnancies that exceed 42 weeks' gestation have increased neonatal morbidity, including convulsions, meconium aspiration, and need for intensive care.7

TIMING OF ELECTIVE INDUCTION

Until recently, elective inductions before 41 weeks' gestation have been controversial because of a lack of evidence. A large randomized trial showed that elective inductions at 39 weeks' gestation or later are associated with improved outcomes in first pregnancies.8 In this trial of low-risk nulliparous women, elective induction at 39 weeks to 39 weeks 4 days had similar neonatal mortality and morbidity as delivery at 40 weeks 5 days or later. Infants from the elective induction group had less need for respiratory support, with a number needed to treat (NNT) of 83 to prevent respiratory support in the first 72 hours of life.

There were also several other improved outcomes with elective induction. Elective induction reduced cesarean delivery (NNT = 28 to prevent one cesarean delivery) and reduced hypertensive pregnancy disorders (NNT = 17).8 The Society for Maternal-Fetal Medicine and the American College of Obstetricians and Gynecologists endorse offering elective induction of labor at 39 weeks' gestation to low-risk nulliparous pregnant individuals under circumstances that are consistent with this trial's study protocol.9,10

INDUCTION OF LABOR AFTER PRIOR CESAREAN DELIVERY

There are several reasons for choosing a trial of labor after a cesarean delivery (TOLAC) instead of a repeat cesarean delivery, including shorter hospital stay, shorter recovery time, and reduced pain after delivery. Careful counseling is required before TOLAC because of risks, including uterine rupture.11,12 A validated calculator is available to assist when deciding on TOLAC vs. a repeat cesarean delivery (https://mfmunetwork.bsc.gwu.edu/web/mfmunetwork/vaginal-birth-after-cesarean-calculator). This calculator was updated to remove the race and ethnicity component, which does not affect the validity.13

For individuals who have had one prior cesarean delivery, TOLAC may reduce rates of cesarean delivery.1416 In 2019, the American Academy of Family Physicians reaffirmed clinical practice guidelines for management of TOLAC (https://www.aafp.org/family-physician/patient-care/clinical-recommendations/all-clinical-recommendations/vaginal-birth-after-cesarean.html). Cervical ripening balloons and oxytocin (Pitocin) are appropriate agents for TOLAC, but prostaglandin use increases the risk of uterine rupture and should be avoided.1,17,18

Already a member/subscriber?  Log In

Subscribe

From $145
  • Immediate, unlimited access to all AFP content
  • More than 130 CME credits/year
  • AAFP app access
  • Print delivery available
Subscribe

Issue Access

$59.95
  • Immediate, unlimited access to this issue's content
  • CME credits
  • AAFP app access
  • Print delivery available

Article Only

$25.95
  • Immediate, unlimited access to just this article
  • CME credits
  • AAFP app access
  • Print delivery available
Purchase Access:  Learn More

Continue Reading

More in AFP

More in Pubmed

Copyright © 2022 by the American Academy of Family Physicians.

This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP.  See permissions for copyright questions and/or permission requests.