Uterine stimulants are used to initiate or augment the labor process. They are used for a variety of reasons, such as to induce labor, to offset the effects of postmaturity on your baby, for blood incompatibilities and fetal-growth impairment, and to strengthen uterine contractions in long labors.
To Initiate The Labor Process
Some practitioners prescribe medications alone to induce labor, while others prefer to manually rupture the membranes. For labor induction to be successful, a woman must be toward the end of her pregnancy and her cervix must be thin, soft, and somewhat dilated. The most common type of uterine stimulant is oxytocin (prepared synthetically as pitocin and syntocinon). Prostaglandins or misoprostil are sometimes used to prepare the cervix and induce labor.
Pitocin and Syntocinon
Oxytocin is a natural hormone, secreted by the pituitary gland, that stimulates uterine muscle contractions. It is injected into the bloodstream in very low doses and under highly supervised hospital conditions at the time of labor and delivery.
Some women note side effects such as anxiety, lower blood pressure, increased heart rate, and excessive uterine contractions. Because it is administered in the hospital, where the side effects may be detected and reported early, there are rarely any long-term risks.
These are naturally occurring hormone-like substances present in various parts of the body. When used to induce labor, they block the release of two hormones – progesterone and relaxin – from the ovaries and stimulate uterine contractions.
Prostaglandins are most often used to induce abortion in early stages of pregnancy, since their side effects, such as nausea, vomiting, and diarrhea, may be extreme later in pregnancy. They are sometimes also given prior to induction to soften or mature the cervix. A relatively new type of induction procedure uses prostaglandin gel, applied directly to the cervix to help soften it and to stimulate the labor process. A new medication, called Misoprostil, is used in a similar manner.