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
High blood pressure with protein in the urine ( preeclampsia Preeclampsia and Eclampsia Preeclampsia is new high blood pressure or worsening of existing high blood pressure that is accompanied by excess protein in the urine and that develops after the 20th week of pregnancy. Eclampsia... read more ) in the woman
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:
The fetus is in an abnormal position Abnormal Position and Presentation of the Fetus Position refers to whether the fetus is facing rearward (toward the woman’s back—that is, face down when the woman lies on her back) or forward (face up). It’s important to check the baby’s... read more or is too large.
The placenta is in the wrong position ( placenta previa Placenta Previa Placenta previa is attachment (implantation) of the placenta over the opening of the cervix, in the lower rather than the upper part of the uterus. Women may have painless, sometimes profuse... read more or vasa previa Vasa Previa In vasa previa, membranes that contain blood vessels connecting the umbilical cord and placenta lie across or near the opening of the cervix—the entrance to the birth canal. Vasa previa may... read more ).
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.
The following is an English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
Childbirth Connection: This web site provide tips for having a healthy baby and safe delivery. The importance of medical care before, during, and after delivery is emphasized.