If a pregnancy isn't proceeding as it should, or if the health of the mother or baby is threatened, doctors have to speed up the process by inducing labor.
Why Is Labor Induced?
According to the CDC, labor is induced in 1 out of 5 pregnancies in the U.S. There are a number of reasons for inducing labor, from medical complications to an overdue baby.
Your doctor might induce labor if:
- You are 1 to 2 weeks past your due date. Past 42 weeks, you and your baby are at greater risk for complications, and the placenta that nourishes your baby in the womb may have diminished so much that it can no longer properly feed your baby. The baby also may breathe in his first bowel movement (called meconium), which can block his airways.
- The membrane that holds the amniotic sac surrounding your baby breaks (your "water breaks") and you don't go into labor on your own (once your water breaks, you and your baby are at greater risk for infection).
- You have a health condition, such as high blood pressure (preeclampsia), gestational diabetes, bleeding, or an infection in your uterus, which puts your health or your baby's health at risk.
- Tests show that your baby is no longer growing or developing at a normal rate, or the baby's heart rate is abnormal.
Sometimes women (or their doctors) decide to induce labor for nonmedical reasons -- for example, they live far away from the hospital and their doctor is worried that they won't get there in time if they do go into labor. Inducing labor for nonmedical reasons is controversial, however, because there are some risks involved. Babies born before 39 weeks are more likely to have health problems and developmental delays.
How Is Labor Induced?
Normally during labor, the lower end of the uterus (cervix) softens. This is called ripening. The cervix thins out (effaces) and opens (dilates). In order for the baby to be born, the cervix must be fully effaced and dilated to allow the baby's head to get through.
Before the doctor will induce labor, he or she will check your cervix and the baby's position to find out whether you are far enough along for induction to work.
Doctors use medications and other methods to efface and dilate the cervix artificially so that the baby can be born. Labor induction techniques include:
Stripping the membranes. The doctor will insert a gloved finger into your vagina and move it back and forth to separate the membrane that connects the amniotic sac to the wall of the uterus. This is called "stripping the membranes," and it causes the body to release hormones called prostaglandins, which ripen the cervix and may lead to contractions. You may feel some cramping and have some spotting after this procedure. Usually this method of inducing labor is done in your doctor's office, and you'll be sent home to wait until contractions begin.
Ripening the cervix. Medications called prostaglandins can dilate your cervix enough to prepare it for labor. Prostaglandins are manufactured versions of chemicals in the body that both ripen the cervix and stimulate the uterus to contract. You take prostaglandins either by mouth or via a gel or suppository inserted in the vagina. (Your doctor shouldn't give you prostaglandins if you've had a previous C-section because of the increased risk of uterine rupture.) Another way to ripen the cervix is by inserting a thin tube called a catheter with a balloon at the tip. When the catheter is placed in your uterus, the balloon is inflated with water, which causes the cervix to expand.
"Breaking your water." If your cervix is already at least partially dilated, your doctor can "break your water" by making a hole in your amniotic sac using a small plastic hook. Once your amniotic sac has broken, you should may having contractions. You'll need to deliver within about 24 hours to prevent infection.
Triggering contractions. The drug Pitocin can bring on contractions to induce or move your labor along. Pitocin is an artificial form of the hormone oxytocin, which triggers and strengthens contractions. It's delivered through an intravenous (IV) tube in your arm. Your doctor will start with a small dose and will gradually increase it until your contractions are strong and frequent enough for the baby to be born.
Aside from stripping the membranes, which is typically performed in the doctor's office, these methods of inducing labor will be done in a hospital where both you and your baby can be carefully monitored.
Some women go into labor and deliver within a few hours after induction of labor begins. Others take one or two days to begin labor. If you don't go into labor with any of these methods, especially once your water is broken, you'll need to have a C-section.