Labor Induction

Labor induction is when steps are taken to cause a pregnant woman to begin the labor process. Most women go into labor on their own between 37 weeks and 42 weeks of the pregnancy. When this does not happen or when there is a medical need, methods may be used to induce labor. Labor induction causes a pregnant woman's uterus to contract. It also causes the cervix to soften (ripen), open (dilate), and thin out (efface). Usually, labor is not induced before 39 weeks of the pregnancy unless there is a problem with the baby or mother.

Before inducing labor, your health care provider will consider a number of factors, including the following:

  • The medical condition of you and the baby.  

  • How many weeks along you are.  

  • The status of the baby's lung maturity.  

  • The condition of the cervix.  

  • The position of the baby.  

WHAT ARE THE REASONS FOR LABOR INDUCTION?

Labor may be induced for the following reasons:

  • The health of the baby or mother is at risk.  

  • The pregnancy is overdue by 1 week or more.  

  • The water breaks but labor does not start on its own.  

  • The mother has a health condition or serious illness, such as high blood pressure, infection, placental abruption, or diabetes.

  • The amniotic fluid amounts are low around the baby.  

  • The baby is distressed.  

Convenience or wanting the baby to be born on a certain date is not a reason for inducing labor.

WHAT METHODS ARE USED FOR LABOR INDUCTION?

Several methods of labor induction may be used, such as:

  • Prostaglandin medicine. This medicine causes the cervix to dilate and ripen. The medicine will also start contractions. It can be taken by mouth or by inserting a suppository into the vagina.  

  • Inserting a thin tube (catheter) with a balloon on the end into the vagina to dilate the cervix. Once inserted, the balloon is expanded with water, which causes the cervix to open.  

  • Stripping the membranes. Your health care provider separates amniotic sac tissue from the cervix, causing the cervix to be stretched and causing the release of a hormone called progesterone. This may cause the uterus to contract. It is often done during an office visit. You will be sent home to wait for the contractions to begin. You will then come in for an induction.  

  • Breaking the water. Your health care provider makes a hole in the amniotic sac using a small instrument. Once the amniotic sac breaks, contractions should begin. This may still take hours to see an effect.  

  • Medicine to trigger or strengthen contractions. This medicine is given through an IV access tube inserted into a vein in your arm.  

All of the methods of induction, besides stripping the membranes, will be done in the hospital. Induction is done in the hospital so that you and the baby can be carefully monitored.

HOW LONG DOES IT TAKE FOR LABOR TO BE INDUCED?

Some inductions can take up to 2–3 days. Depending on the cervix, it usually takes less time. It takes longer when you are induced early in the pregnancy or if this is your first pregnancy. If a mother is still pregnant and the induction has been going on for 2–3 days, either the mother will be sent home or a cesarean delivery will be needed.

WHAT ARE THE RISKS ASSOCIATED WITH LABOR INDUCTION?

Some of the risks of induction include:

  • Changes in fetal heart rate, such as too high, too low, or erratic.  

  • Fetal distress.  

  • Chance of infection for the mother and baby.  

  • Increased chance of having a cesarean delivery.  

  • Breaking off (abruption) of the placenta from the uterus (rare).  

  • Uterine rupture (very rare).  

When induction is needed for medical reasons, the benefits of induction may outweigh the risks.

WHAT ARE SOME REASONS FOR NOT INDUCING LABOR?

Labor induction should not be done if:

  • It is shown that your baby does not tolerate labor.  

  • You have had previous surgeries on your uterus, such as a myomectomy or the removal of fibroids.  

  • Your placenta lies very low in the uterus and blocks the opening of the cervix (placenta previa).  

  • Your baby is not in a head-down position.  

  • The umbilical cord drops down into the birth canal in front of the baby. This could cut off the baby's blood and oxygen supply.  

  • You have had a previous cesarean delivery.  

  • There are unusual circumstances, such as the baby being extremely premature.