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Induction of Labor


Julie S. Moldenhauer

, MD, Children's Hospital of Philadelphia

Reviewed/Revised Jul 2021 | Modified Sep 2022
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Induction of labor is stimulation of uterine contractions before spontaneous labor to achieve vaginal delivery.


Induction of labor can be

Before elective induction, gestational age must be determined. Commonly, elective induction has been avoided at 39 weeks because of lack of evidence for perinatal benefit and concern about a higher frequency of cesarean deliveries and other adverse outcomes. This practice may be changing, partly because a 2018 study showed that induction of low-risk women at 39 weeks reduced the frequency of cesarean deliveries (but not perinatal adverse outcomes) compared with expectant management (1 Indications reference Induction of labor is stimulation of uterine contractions before spontaneous labor to achieve vaginal delivery. Induction of labor can be Medically indicated (eg, for preeclampsia or fetal compromise)... read more ).

Contraindications to induction include having or having had the following:

Multiple prior uterine scars and breech presentation are relative contraindications.

Indications reference


If the cervix is closed, long, and firm (unfavorable), the goal is to cause the cervix to open and become effaced (favorable). Various pharmacologic or mechanical methods can be used. They include

Once the cervix is favorable, labor is induced.

Constant IV infusion of oxytocin is the most commonly used method; it is safe and cost-effective. Low-dose oxytocin is given at 0.5 to 2 milliunits/minute, increased by 1 to 2 milliunits/minute, usually every 15 to 60 minutes. High-dose oxytocin is given at 6 milliunits/minute, increased by 1 to 6 milliunits/minute every 15 to 40 minutes to a maximum of 40 milliunits/minute. With doses > 40 milliunits/minute, excessive water retention may lead to water intoxication. Use of oxytocin must be supervised to prevent uterine tachysystole (> 5 contractions in 10 minutes averaged over 30 minutes), which may compromise the fetus.

External fetal monitoring Fetal Monitoring Labor consists of a series of rhythmic, involuntary or medically induced contractions of the uterus that result in effacement (thinning and shortening) and dilation of the uterine cervix. The... read more is routine; after amniotomy (deliberate rupture of the membranes), internal monitoring may be indicated if fetal status cannot be assessed externally. Amniotomy can be done to augment labor when the fetal head is applied to a favorable cervix and not ballotable (not floating).

Technique reference

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