Induction and Augmentation of Labor
Occasionally, the labor itself needs assistance, either in getting started or in progressing. There are several commonly used methods for each.
An induced labor is started artificially, by either chemical or physical stimulation. Induction is medically indicated in situations where continuing the pregnancy would adversely affect either the woman or baby. Such situations include:
- Rh sensitization (incompatibility),
- prolonged rupture of the membranes with no labor starting,
- and fetal death.
When the amniotic sac breaks prior to labor, it is known as premature rupture of the membranes (PROM). In many cases, the cause of PROM is unknown, but research indicates that PROM may be caused by an infection, such as group B strep. Whether or not you are induced depends on the week of gestation during which PROM occurs.
At term, most labors will naturally start within 6 to 12 hours. If not, most caregivers will want to induce labor to prevent infection. Some studies indicate that women can safely wait for labor to begin even after 24 hours of the membranes rupturing, provided that no vaginal exams are performed and that the woman is monitored for infection.
If PROM occurs between 24 and 33 weeks gestation, the physician will need to weigh the risks of infection and prematurity. Women are usually placed on bed rest and closely monitored for infection. The fetus is evaluated for lung maturity, and steroids are usually administered to the woman to promote fetal lung development. Labor can be induced either when the fetus is mature enough for delivery or if the woman shows clinical signs of infection. Amnioinfusion can be performed during labor to provide additional fluid in the uterus.
- Expect stronger contractions.
- Be an active coach.
- Prepare her for the next contraction by watching the monitor and alerting her when the contraction begins.
- Do not leave her alone.
Caregivers use a number of techniques to induce labor. The simplest technique is called stripping the membranes and is done by the caregiver during a vaginal exam. He inserts his lingers between the partially dilated cervix and the amniotic sac, which irritates and loosens the sac from the uterine wall. This causes a release of prostaglandins. Some women feel a burning or stinging sensation or even pain when this is done. However, unless labor is imminent, this procedure does not initiate true labor, although it may cause contractions for a time.
Another physical method of inducing labor is amniotomy, the artificial rupture of the membranes. This is done by inserting an amnihook, a long hookfike instrument, through the vagina and partially dilated cervix, and making a tear in the amniotic membranes. The procedure is no more painful than a vaginal exam because the membranes do not contain any nerves, but it does present some risks. If labor does not begin, both the woman and baby are exposed to an increased chance of Infection and to the use of Pitocin. If Pitocin does not produce results within 24 hours, a cesarean delivery is usually performed.
Prostaglandin applied either in or on the cervix helps to ripen the cervix and increase the success of an induction. However, it can also cause strong contractions, nausea, vomiting, diarrhea, fever, and chills. Prostaglandin gel is not recommended for use with women who have a fundal scar, history of asthma, or glaucoma.
Caregivers most frequently induce labor through the use of Pitocin. Pitocin, a synthetic form of the hormone oxytocin, should always be administered through an Intravenous drip that is electronically monitored. Some doctors also place a pressure catheter inside the uterus to determine contraction strength.
Labor should never be induced simply for convenience because induction increases the risks to both the woman and the fetus. For this reason, the FDA’s Obstetric-Gynecologic Advisory Committee voted to withdraw FDA approval of the use of oxytocic drugs for elective induction of labor. Interestingly, since the late 1980s, weekend births have declined with a corresponding increase during the week. A 3-year investigation of birth certificate records showed that this increase was a result of an increased number of inductions. In addition, the number of cesareans because of failed inductions also increased.
In a natural labor, the oxygen supply to the fetus is decreased during each contraction. The long, intense contractions of an induced labor can deprive the fetus of even more oxygen, resulting possibly in fetal distress and a cesarean birth. An overdose of Pitocin, resulting in tetanic or continuous contractions, can cause premature separation of the placenta from the uterus or even uterine rupture. These conditions could disrupt the oxygen supply to the fetus and lead to an emergency cesarean delivery if a vaginal birth cannot be effected immediately. Other maternal side effects include lowered blood pressure, rapid heart rate, anxiety, and swelling. Also associated with the use of Pitocin is increased jaundice in the newborn.
Induced contractions tend to start out much stronger than natural contractions. The gradual buildup of labor is not present. Induced contractions come more frequently, last longer, and often peak immediately rather than in the middle of the contraction. They make labor much more difficult to manage. If your labor is induced, you must stay on top of the contractions from the very beginning or you may lose control. Your partner is extremely important in this kind of labor. He can watch the monitor to observe the contractions so that he can prepare you for the start of each contraction. If a contraction lasts longer than 2 minutes, he must immediately alert the nursing staff. His encouragement and support are essential. You should not be left alone because panic and loss of control usually result. If your partner must leave you to use the bathroom or get something to eat, ask a nurse to stand in. Because of the strength of the contractions, you may need to use advanced breathing techniques sooner and for a longer time, which can he very tiring. Your partner’s assistance in keeping you comfortable and relaxed will help you to conserve the energy that you will need for birth.
If your caregiver feels that your labor is not progressing normally, he may decide to augment it (speed it up). The timetables used to determine normal labor are based on averages, and very few women are “average.” Before you agree to any kind of intervention, ask for a little more time and try some noninvasive techniques. Some popular natural technlques to speed up labor are walking, a warm shower or bath, changing position, acupressure, loving support (including hugs, caresses, and words of encouragement), and nipple stimulation to release natural oxytocin. If anyone in the room is causing you stress, ask that person to leave.
If natural measures do not speed up your labor, your caregiver may want to perform an amniotomy. Amniotomy to augment labor carries the same risks it does when used to induce labor. In addition, it removes the protective buffer of fluid between the baby’s head and toe cervix. As a result, babies who go through labor for an extended period of time with the membranes ruptured experience more head molding and caput succedaneum (swelling of the soft tissues of the scalp), as well as possible cephalhematoma (a lump or swelling on the scalp that is filled with blood). None of these are dangerous, although a caput succedaneum normally takes several days to subside, while a cephalhematoma may take months to reabsorb.
Some studies show that amniotomy does not significantly affect the progress of labor. The contractions often increase in intensity and duration for a while after the procedure is performed, but the average difference in the length of labor is only 50 minutes. In addition, the labor may become uncomfortable and more difficult to control. A drop in the fetal heart rate is also associated with the procedure.
If your caregiver suspects fetal distress, he will need to perform an amniotomy to insert an internal fetal monitor or to obtain a fetal blood sample to measure the pH of toe infant’s blood. He may also want to check for the presence of meconium in the fluid, Otherwise, you have the right to reject this procedure.
If you have an amniotomy done, but it does not speed up your labor, your caregiver may start a Pitocin IV drip to stimulate your uterus to produce more efficient contractions. Be prepared for stronger and more frequent contractions, the same as in an induced labor. You may need to begin using advanced breathing techniques to stay on top of toe contractions. The risks associated with the use of Pitocin are the same for augmentation of labor as they are for induction of labor.