Usually, labor is induced by giving the woman oxytocin, a drug that makes the uterus contract more frequently and more forcefully. The oxytocin given is identical to the natural oxytocin produced by the pituitary gland. It is given intravenously with an infusion pump, so that the amount of drug given can be controlled precisely.
Before contractions of the uterus can be induced, the cervix must be thinned (effaced) and ready to open (dilate) so that the baby can be delivered. Several techniques can be used to help the cervix efface and dilate:
A prostaglandin (such as misoprostol) may be given vaginally.
A thin, flexible tube (catheter) with a balloon attached can be inserted into the cervix. The balloon is inflated to put gentle pressure on and thus dilate the cervix.
Dried seaweed stems (laminaria) may be inserted into the cervix. The laminaria absorb fluids and then expand, thus dilating the cervix.
Problems that usually require induction of labor include
Sometimes labor is induced for reasons unrelated to a health issue. For example, labor may be induced when a woman has a history of rapid deliveries. In such cases, inducing labor means that a doctor or other health care practitioner can be present to deliver the baby.
Labor is not induced in the following circumstances:
Throughout induction and labor, the fetus’s heart rate is monitored electronically. At first, a monitor is placed on the woman’s abdomen. Occasionally, after the membranes are ruptured, an internal monitor is inserted through the vagina and attached to the fetus’s scalp.
If induction is unsuccessful, the baby is delivered by cesarean.