Past DueHeather Turgeon
Inducing labor or letting baby come on her own — it’s a choice that a lot of moms and doctors have to make. A little help during delivery isn’t a new concept. Pitocin, the synthetic form of oxytocin (which spurs contractions) has been used since roughly the 1960s to start or speed up the process of labor. For centuries before that, doctors and midwives used mechanical means (for example, rupturing the amniotic sac) to encourage labor when mom or baby’s health was at risk.
In more recent years, there’s been a spike in the number of inductions. According to the CDC, in 1990 the rate of induction was roughly 9.5 percent of all births, whereas in 2008, it was 23 percent. That could even be an underestimate; one recent, large study found a 44 percent induction rate among delivering moms.
With more and more births being nudged along, it’s clear that there is a downside, too. Doctors usually cite medical reasons for inducing, but those reasons are often subjective ones (such as the judgment that baby is too big or that labor isn’t progressing fast enough), so researchers and clinicians are weighing the benefits and risks to figure out the best practice guidelines.
“Due window” instead of “due date”
When I was pregnant with my first baby and my due date had come and gone, I remember having the distinct thought, “Will I be the first woman in history to never actually give birth?” The lead-up to birth is such an emotional and physical build-up that many of us feel behind the clock when we’re far from it. As the third trimester ends, friends and family clamor around excitedly with, “Any news?” and “Wow, you look like you couldn’t go another day!” Meanwhile, the big day could be weeks away.
A due date is misleading, because most babies arrive in a due window of 38-42 weeks. Doctors usually choose to induce, if labor hasn’t started, between weeks 41-42 (after this, the baby’s size and the placenta’s decreasing ability to supply nutrients can pose a risk), so this is really the date by which your baby is “due” to the world. It’s nearly impossible to tell when you’ll actually give birth — although if this is a second or later pregnancy, remember that babies tend to come roughly when their older siblings did. Your doctor will start to check your cervix for signs of readiness, but you could walk around two centimeters dilated for weeks, or you could have no cervical changes and be in labor the next day.
As pregnant women, we may be X-ing off the calendar days in anticipation, but babies have their own plans. Scientists don’t know exactly what causes labor to begin, but they are getting closer to figuring out this complex cascade of chemical events. The body has an intricate, built-in way of triggering the labor process, and part of the signal that trips off this process could come from the baby, who is adding neural connections and putting the finishing touches on her little lungs and other organs. This is why the Mayo Clinic says that, “up to two weeks after your due date, a wait-and-see approach might be preferable.” And the American Congress of Obstetricians and Gynecologists recommends that elective induction shouldn’t happen before 39 weeks.
As you get closer to delivery, there are plenty of reasons your doctor might mention the idea of induction. For example:
- You are approaching 42 weeks. After this, baby’s growing size and the decreasing effectiveness of the placenta can pose a risk to the health of both mom and baby.
- Your water has broken, but there are no contractions, as the risk of infection goes up if you wait too long to get baby out.
- Your baby’s size. If her growth is slowing, your doctor might think about delivering early.
- Your amniotic fluid is low (less than 5 cm as a measurement is considered low).
- You develop preeclampsia or have another illness that could compromise the health of your baby
- Elective induction. In some cases, schedules, life circumstances, or patient preference may lead a woman and her doctor to make this decision, although it is controversial.
Induction does carry its own risks, too. Some of the risks that may be associated with inducing labor are:
C-section: Being induced is associated with a higher risk of C-section. For example, a 2010 study in the journal Obstetrics & Gynecology looked at a sample of almost 8,000 women and found that induction upped the risk of C-section, even after adjusting for complications and medical risks. The authors estimate that inductions contributed 20 percent to Cesarean sections. And earlier this year, researchers reported that the risk of C-section went up by 67 percent when labor was induced without a medical reason. “The chance of having a Cesarean delivery is greatly increased for first-time mothers who have labor induction, especially if the cervix is not ready for labor,” concludes the ACOG.
Infection: The risk of infection for both mom and baby goes up if there is too much time in between rupturing the amniotic sac and delivering the baby.
Umbilical cord problems: In some cases, the umbilical cord can slip into the vagina before delivery. When the cord is compressed, it decreases baby’s oxygen.
Changes in the fetal heart rate: The medication used to induce labor can cause heavy contractions, which can decrease baby’s oxygen and lower heart rate.
Bleeding: Inducing increases the risk that the uterine muscles will not contract sufficiently, which can lead to serious bleeding.
What to expect
If you are induced, you’ll receive/undergo one or more of the following medications and procedures:
Oxytocin: Usually referred to by the brand name Pitocin, this drug is delivered by IV and causes contractions of the uterus. It can be used to start labor, or to speed up or intensify labor. This is a synthetic version of a naturally occurring hormone.
Prostaglandins: If your cervix isn’t showing signs of being ready for labor, in some cases a doctor may use hormones called prostaglandins to “ripen” the cervix before inducing. Another option is to use a catheter with a small balloon at the end, which, when inflated with water, also stimulates the body’s natural production of prostaglandins.
Stripping the membranes: If your doctor sweeps a gloved finger over the thin membranes that connect the amniotic sac to the wall of your uterus, your body may produce prostaglandins, causing the cervix to soften and possibly encourage contractions.
IV and continuous fetal heart monitor: When you’re induced, you’ll be given an IV as well and asked to sit or lie down while the hormones do their job. Your baby’s heart rate will also be closely monitored.
There’s no doubt that sometimes induction is the best bet, and only you and your doctor have the information to make that call. But it helps to know — by asking and pressing your doctor — whether induction is a medical necessity, or if it’s a subjective, grey area in which your personal preferences should have weight. Though statistics are trending towards making induction more commonplace, in the absence of a solid medical reason, research seems to be pointing in the direction of a wait-for-baby approach.