Induction of labor refers to the use of medications or other methods to induce, or cause, labor. This practice is used to make contractions start so that delivery can occur.1
Induction is usually used only when a problem with the pregnancy risks the health of either the mother or the fetus or when the due date has passed.2
Several weeks before labor begins, the cervix begins to soften (called "ripening"), thin out, and open to prepare for delivery. If the cervix is not ready, especially if labor has not started 2 weeks or more after the due date, a health care provider may recommend medication or other means to ripen the cervix before inducing labor.
Health care providers use a scoring system, called the Bishop score, to determine how ready the cervix is for labor. The scores range from 0 to 13. A score of less than 6 means that the cervix may need help to prepare for labor.1
- Stripping the membranes. The health care provider can separate the thin tissue of the amniotic sac, which contains the fetus, from the wall of the uterus. This process causes the body to release prostaglandins (pronounced pros-tuh-GLAN-dins), which soften the cervix and cause contractions.
- Giving prostaglandins. This drug may be inserted into the vagina or given by mouth. The body naturally makes these chemicals to ripen the cervix, but sometimes additional amounts are needed to help labor occur.
- Inserting a catheter. A small tube with an inflatable balloon on the end can be placed in the cervix to widen it.
Once the cervix is ripe, a health care provider may recommend one of the following techniques to start contractions or to make them stronger:1
- Amniotomy (pronounced am-nee-OT-uh-mee). A health care provider uses a tool to make a small hole in the amniotic sac, causing it to rupture (or the water to break) and contractions to start.
- Giving oxytocin (also called Pitocin). Oxytocin is a hormone the body naturally makes that causes contractions. It is given to start labor or to speed up labor that has already begun.
In most cases, induction is limited to situations in which there is a problem with the pregnancy or in which the pregnancy has continued past the infant's due date. It is usually best to "let the baby set the delivery date" and allow labor to begin on its own, unless there is a medical reason to do otherwise.
- American College of Obstetricians and Gynecologists. (2012). FAQ: Labor induction. Retrieved February 20, 2017, from https://www.acog.org/Patients/FAQs/Labor-Induction
- American College of Obstetricians and Gynecologists. (2009). ACOG issues revision of labor induction guidelines. Retrieved February 20, 2017, from http://www.acog.org/About-ACOG/News-Room/News-Releases/2009/ACOG-Issues-Revision-of-Labor-Induction-Guidelines
- American College of Nurse-Midwives. (2016). Position statement: Induction of labor. Retrieved February 17, 2017, from http://www.midwife.org/ACNM/files/ACNMLibraryData/UPLOADFILENAME/000000000235/Induction-of-Labor-2016.pdf (PDF – 270 KB)