What does it mean to induce labor? If your labor doesn't start on its own, your practitioner can use medication and other techniques to bring on (or induce) contractions. She can use some of the same methods to augment, or speed up, your labor if it stops progressing for some reason. In 2006, according to the U.S. Centers for Disease Control and Prevention, more than 1 in 5 births in the United States was induced. This rate more than doubled from 1990.
Why would my labour be induced?
Your practitioner will recommend induction when the risks of waiting for labor to start on its own are higher than the risks of the procedures used to get your labor going. This may be the case when:
• You're still pregnant one to two weeks past your due date. Experts advise waiting no longer than that to give birth because it puts you and your baby at greater risk for a host of problems. For example, the placenta may become less effective at delivering nutrients to your baby, increasing the risk of a stillbirth or serious problems for your newborn.
In addition, if your baby gets too big, your labor is more likely to be prolonged or stalled, your chances of needing a c-section are higher, and both you and your baby have an increased risk of injury during a vaginal delivery.
• Your water breaks and your labor doesn't start on its own. In this case, you'll be induced to decrease the risk of infection to your uterus and your baby, which is more of a concern once your membranes have ruptured. (However, if your baby is still very premature, your practitioner may hold off on inducing labor.)
• Tests show that your placenta is no longer functioning properly, you have too little amniotic fluid, or your baby isn't thriving or growing as he should.
• You develop preeclampsia, a serious condition that can endanger your health and restrict the flow of blood to your baby.
• You have a chronic or acute illness – such as high blood pressure, diabetes, or kidney disease – that threatens your health or the health of your baby.
• You've previously had a full-term stillbirth.
You may also be induced for logistical reasons -- for example, if you live far away from the hospital or have very rapid labors. In this situation, your practitioner will schedule your induction for no earlier than 39 weeks, unless fetal lung maturity testing (which requires amniocentesis) indicates it's safe to induce before then. This minimizes the risk of inducing a baby whose lungs are not yet fully mature.
What are some of the techniques used to induce labour?
This depends in large part on the condition of your cervix at the time. If your cervix hasn't started to soften, efface (thin out), or dilate (open up), it's considered "unripe" – or not yet ready for labor.
In that case, your practitioner would use either hormones or "mechanical" methods to ripen your cervix before the induction. This tends to shorten the length of labor, and sometimes these procedures end up jump-starting your labor as well.
If your labor doesn't start, you'll get an IV infusion of oxytocin. This drug (often referred to by the brand name Pitocin) is a synthetic form of the hormone that your body naturally produces during spontaneous labor.
Some of the methods used to ripen the cervix and induce labor are:
• Using prostaglandins. Typically, if you need to be induced but your cervix is not yet dilated or thinned out, you'll be admitted to the hospital and your caregiver will start the induction by inserting medication that contains prostaglandins into your vagina. This medication helps to ripen the cervix and, as mentioned above, sometimes stimulates enough contractions so that you don't need oxytocin.
• Using a Foley catheter. Instead of using medication to ripen your cervix, your practitioner may insert a catheter with a very small uninflated balloon at the end into your cervix. When the balloon is inflated with water, it puts pressure on your cervix, stimulating the release of prostaglandins, which cause the cervix to open and soften. When your cervix begins to dilate, the balloon falls out and the catheter is removed.
• Stripping or sweeping the membranes. If your cervix is already somewhat dilated and there's no urgent reason to induce, your practitioner can insert her finger through the cervix and manually separate your amniotic sac from the lower part of your uterus. This causes the release of prostaglandins, which may help further ripen your cervix and possibly get contractions going.
In most cases, this procedure is done during an office visit. You're then sent home to wait for labor to start, usually within the next few days. Many moms-to-be find this procedure uncomfortable or even painful, although the discomfort is short-lived.
• Rupturing the membranes. If you're at least a few centimeters dilated, your practitioner can insert a small, plastic hooked instrument through the cervix to break your amniotic sac. This procedure (called amniotomy) causes no more discomfort than a vaginal exam.
If your cervix is very ripe and ready for labor, there's a small chance that rupturing the membranes alone will be enough to get your contractions going. If that doesn't happen, your practitioner will give you oxytocin through an IV.
Once your water has broken, most practitioners will want you to deliver within 12 to 24 hours because the risk of infection for you and your baby increases over time.
• Using oxytocin (Pitocin). Your practitioner may give you oxytocin through an IV pump to start or augment your contractions. She can adjust the amount you need according to how your labor progresses.
What risks are associated with inducing labour?
While induction is generally safe, it does carry some risk, which may vary according to the methods used and your individual situation. Oxytocin, prostaglandins, or nipple stimulation (explained below) occasionally cause contractions that come too frequently or are abnormally long and strong. This in turn may stress your baby.
In rare cases, prostaglandins or oxytocin also cause placental abruption or even uterine rupture, although ruptures are extremely rare in women who've never had a c-section or other uterine surgery.
One commonly used prostaglandin, misoprostol, is associated with a relatively high rate of rupture in women attempting a vaginal birth after a cesarean (VBAC) and should never be used in women with a scarred uterus. Some experts don't think women attempting VBAC should be induced with oxytocin, either.
To assess the frequency and length of your contractions as well as your baby's heart rate, you'll need to have continuous electronic fetal monitoring during an induced labor. You'll probably have to lie or sit while being monitored, but some hospitals offer telemetry, which lets you walk around during the process.
Inducing labor can take a long time, particularly if you start with an unripe cervix, and this process can be hard on you and your partner psychologically. (On the other hand, among women who go past their due date, the seemingly endless wait for labor to begin may be even more trying.)
And if the induction doesn't work, you'll need a c-section. Having a c-section after a long labor or unsuccessful induction is associated with higher rates of complications than you'd face with a planned c-section.
Remember that your practitioner will recommend inducing your labor only when she believes that the risks to you and your baby of waiting for labor to begin on its own are higher than the risks of intervening.
Are there any circumstances in which my labour shouldn't be induced?
Yes. You'll need to have a c-section rather than an induction whenever it would be unsafe to labor and deliver vaginally, including the following situations:
• Tests indicate that your baby needs to be delivered immediately or can't tolerate contractions.
• You have a placenta previa (when the placenta is lying unusually low in your uterus, either next to or covering your cervix).
• Your baby is in a breech or transverse position, meaning that he's not coming headfirst.
• You've had more than one c-section. (Some practitioners believe that women with even one previous c-section shouldn't be induced.)
• You had a previous c-section with a "classical" (vertical) uterine incision or other uterine surgery, such as a myomectomy (surgery to remove fibroids).
• You're having twins and the first baby is breech, or you're having triplets or more.
• You have an active genital herpes infection.
Are there any techniques I can try at home to get my labour going?
No do-it-yourself methods have been proven consistently to be both safe and effective. Here's the scoop on some of the techniques you may have heard about:
• Sexual intercourse: Semen contains some prostaglandins and having an orgasm may stimulate some contractions. A few studies have shown that having sex at term may decrease the need for labor induction, but others have found no effect on promoting labor.
• Nipple stimulation: Stimulating your nipples releases oxytocin and may help start labor. While it's a time-honored approach, more research is needed to determine how effective it is. And because there's a possibility of overstimulating your uterus (and stressing your baby), it's not something you'd want to try without being monitored. Sometimes – more often when the end of labor is in sight – a practitioner will suggest nipple stimulation to provide a little extra help with contractions.
• Castor oil: Castor oil is a strong laxative. Although stimulating your bowels may cause some contractions, there's no definitive proof that it helps induce labor – and you're likely to find the effect on your gut very unpleasant.
• Herbal remedies. A variety of herbs are touted as useful for labor induction, but there isn't enough evidence to prove that any of them are both safe and effective. Some are risky because they can overstimulate your uterus and may be unsafe for your baby for other reasons as well.