Induced Labor
From Encyclopedia of Sex and Sexuality
The initiation of labor by medical means rather than the spontaneous onset of labor. A number of choices are available to induce, or stimulate, labor. The most common method is the infusion of a dilute solution of oxytocin, a hormone produced in the pituitary gland, into a maternal vein, causing uterine contractions. One stimulus for the release of oxytocin is breast stimulation, resulting in the very common occurrence of uterine contractions following nipple stimulation or nursing.
A second method for the induction of labor is rupture of the fetal membranes. This can be done with either a needle or a small sharp instrument designed especially for that purpose. The cervix must be partially dilated and the presenting part of the fetus (the body part that will emerge first at delivery) should be well engaged in the pelvis so that when the membranes rupture, the umbilical cord does not descend into the vagina with the escaping amniotic fluid. In a patient with a thinned and dilated cervix, rupture of the membranes is an effective method of inducing labor and the use of oxytocin is usually not required.
A third way to induce labor is placing prostaglandin, a potent uterine contractor, into either the cervix or the vagina to induce uterine contractions. The action of prostaglandin is much more difficult to control than the intravenous infusion of oxytocin and is, therefore, less common, but it is sometimes used to help in the dilation of the cervix.
