Induction: a word that can incite strong feelings in either direction for pregnant women. Maybe you brought the topic up to your doctor, maybe she brought it up to you. The idea of being induced and meeting your baby sooner may sound exciting (not to mention the relief of not being pregnant anymore!). Or maybe you feel scared at the prospect of an induction replacing the natural birth you pictured yourself having. Let’s talk over the reasons you might be induced, plus a well-known research study called the ARRIVE trial about whether to induce a healthy pregnancy at 39 weeks.
Labor induction rates have skyrocketed in the last 30 years
In 2022, 35.7% of black pregnant women and 41.9% of white pregnant women were induced. That rate has tripled in the last 30 years [1]. Some inductions are elective, meaning that a pregnant woman requests to have an induction for personal reasons, such as living far away from a hospital, having family in town to help for a certain length of time, wanting to be sure to deliver her baby when her doctor will be available, or other reasons.
Some inductions are medically indicated. This means that under some circumstances, the benefits of waiting for labor to begin on its own are outweighed by the risks. This may be the case when the mother and/or baby’s life is threatened by an issue that only delivery can solve, such as preeclampsia (which can be severely dangerous to both mother and baby)..
Medical reasons to be induced
Other potential medical indications for labor induction include certain pregnancy disorders, such as gestational diabetes, oligohydramnios (not enough amniotic fluid in the uterus), an infection of the uterus, placental abruption (when the placenta detaches from the wall of the uterus), or fetal growth restriction (baby isn’t growing normally in the womb anymore because of a placenta problem). If a woman’s water breaks but labor hasn’t started within a certain amount of time, she might also be induced to avoid infection.
Other common reasons to be induced
Two other common reasons for induction are due to concerns over a baby’s large estimated size (fears of a “big baby”), or because the mother is past her estimated due date.
What are the reasons you might be induced?
You have a pregnancy or other health complication
If you are looking at induction due to a pregnancy complication or a separate medical reason such as needing to start cancer treatment, it’s important to discuss with your provider the risks and benefits of an induction for your specific case. While there are well-documented risks for induction before 39 weeks, some diagnoses like preeclampsia might require an earlier delivery to prevent maternal death or serious illness. Each pregnancy complication is different and the question of induction might be more or less serious depending on your situation. Keep in mind, too, that your doctor or healthcare provider can usually offer you estimates or percentages (not guarantees) of the likelihood that something will happen if you don’t induce labor.
Baby is sick or not growing properly
Sometimes a baby is not growing properly, which is usually due to a placental problem. Some babies may also require medical intervention to diagnose or treat a serious condition or disease. For example, Natural Womanhood Managing Editor Anne Marie Williams was induced at 38 weeks to get better imaging of a large cyst on her preborn daughter’s ovary. The day after birth, her baby had an ultrasound, and the day after that, she had surgery. As with pregnancy complications, talk to your doctor about the risks and benefits in your and your baby’s particular case.
Your water broke but labor hasn’t started
If your water breaks but labor doesn’t start within a certain timeframe—often 24 hours— many doctors will encourage induction. This potential scenario is especially important to consider and discuss with your doctor in advance; say, during one of your third trimester checkups. Evidence-Based Birth has a helpful explainer here on “the 24 hour clock for PROM [premature rupture of membranes]” and what the science says about how long you have before you should be induced if your baby is 37 weeks gestation or beyond. Wondering how this affects you if you’ve experienced preterm premature rupture of membranes (PPROM)? Check out this article for further guidance.
Baby might be big
This reason to be induced no longer recommended by the American College of Obstetricians and Gynecologists (ACOG). If your provider suggests induction to you because of a large estimated size of your baby, check out this article from Natural Womanhood (and consider sharing it with your provider!). It explains why ACOG no longer recommends induction for suspected macrosomia, and what they encourage instead.
Baby is overdue
If you are entering your 41st week of pregnancy and still have no signs of labor, you will probably begin to consider whether or not you’d like an induction. Some providers prefer an “expectant management” approach, meaning that you will be closely monitored in your 41st (or even 42nd, in some cases) week of pregnancy, and allowed to go into labor naturally until you reach a certain point. Other providers prefer to induce as soon as you go “overdue.”
Estimated due dates are just that—estimates. They can often be incorrect, and babies rarely come on a perfect schedule. However, there is data to suggest that the absolute risk of stillbirth does increase after you pass your due date. In this meta-analysis of thirteen studies analyzing 15 million total pregnancies, researchers found that the risk of stillbirth increased after 41 weeks of gestation (compared to women who delivered at 40 weeks) [2]. They found that there was one additional stillbirth for every 1,449 pregnancies analyzed.
The ARRIVE trial: What does research say about the benefits of induction before your due date?
On that note, a commonly-cited study looking at gestational ages (lengths of pregnancy) and risk for stillbirth or other negative outcomes is known as the ARRIVE trial, which stands for A Randomized Trial of Induction Versus Expectant Management [3]. In this 2018 study, researchers randomly assigned 3,062 low-risk women pregnant with their first babies to be induced at 39 weeks, and the remaining 3,044 participants to be managed expectantly, meaning that they could either wait for labor to begin on its own, be induced for medical reasons, or be induced by choice after they were 40 weeks and 5 days gestation.
Inducing at 39 weeks did not decrease the chances of stillbirth or neonatal death by any significant margin. But there was a lower rate of Cesarean section than for the expectant management group: 22.2% of the expectant management group ended up delivering via C-section, versus 18.6% of those who were induced at 39 weeks. Early-induced mothers also had a lower chance of developing high blood pressure near the end of their pregnancies and spent less time in the hospital after giving birth.
So should women with healthy pregnancies be induced at 39 weeks?
A 2024 Australian research study contradicted the ARRIVE trial’s results, finding that conventional wisdom about inductions and C-sections was right. Women who had elective (not medically indicated) inductions were more likely to end up with C-sections than women who went into labor on their own. Around one-fifth of all inductions end in a Cesarean birth, and this makes sense.. Induction is inherently a more medicalized birth with more interventions [4].
Say you’re overdue. Should you be induced at 41 weeks rather than continuing to wait for labor?
Many studies have looked at both maternal and fetal outcomes for women who elect for induction at 41 weeks rather than expectant management. According to the research compiled here by Evidence Based Birth, inducing at 41 weeks has the benefit of having a decreased risk of stillbirth compared to the risk at 42 weeks. (Again, the risk for stillbirth increases slightly the further you go after 39 weeks.)
However, getting an induction at 41 weeks (or at any time during your pregnancy) does predispose you to the cascade of interventions, where one medical intervention brings on more interventions—such as needing an epidural due to the more painful contractions caused by the Pitocin you’ve received for your induction [5]. You also miss out on the hormonal benefits of spontaneous labor when you are induced [6].
The bottom line
There’s a whole range of reasons you might be induced. If having a more natural or unmedicated childbirth is important to you, it might be more difficult to have that experience in an induction, no matter how far along you are. No matter if you might have a “big baby,” are past your due date, or are having pregnancy complications, it’s important to understand the benefits and risks of an induction before you make your choice. That being said—data is helpful, but it cannot guarantee how your specific induction or natural birth will turn out.
In part II, we’ll discuss the methods of induction, so you can more fully understand what induction might look like for you.
This article was updated on Sept 18, 2024, to reflect new data about elective labor induction and C-section rates.
References:
[1] Simpson, Kathleen Rice. “Trends in Labor Induction in the United States, 1989 to 2020.” MCN. The American journal of maternal child nursing vol. 47,4 (2022): 235. doi:10.1097/NMC.0000000000000824 [2] Muglu, Javaid et al. “Risks of stillbirth and neonatal death with advancing gestation at term: A systematic review and meta-analysis of cohort studies of 15 million pregnancies.” PLoS medicine vol. 16,7 e1002838. 2 Jul. 2019, doi:10.1371/journal.pmed.1002838 [3] Grobman, William A et al. “Labor Induction versus Expectant Management in Low-Risk Nulliparous Women.” The New England journal of medicine vol. 379,6 (2018): 513-523. doi:10.1056/NEJMoa1800566 [4] Kamel, Rasha A et al. “Predicting cesarean delivery for failure to progress as an outcome of labor induction in term singleton pregnancy.” American journal of obstetrics and gynecology vol. 224,6 (2021): 609.e1-609.e11. doi:10.1016/j.ajog.2020.12.1212 [5] Lothian JA. Saying “No” to Induction. J Perinat Educ. 2006 Spring;15(2):43–5. doi: 10.1624/105812406X107816. PMCID: PMC1595289. [6] Amis D. Healthy birth practice #1: let labor begin on its own. J Perinat Educ. 2014 Fall;23(4):178-87. doi: 10.1891/1058-1243.23.4.178. PMID: 25411537; PMCID: PMC4235056.
