Natural-birth advocates consider labor induction one of the main elements of the “cascade of interventions” modern medicine uses to assist—or alter, depending on one’s view of it—the process of childbirth.
Doctors say they induce labor to save the lives of mothers and children, and to help ease otherwise prolonged labor pains.
One of the most debated aspects of inductions: whether they increase the risk of caesarean deliveries, or C-sections. Most studies have contradicted one another and been generally inconclusive. A study published this week in the New England Journal on Medicine may have brought much needed clarity to the field.
From an initial pool of about 23,000 randomly selected low-risk first-time mothers, 6,000 opted to participate in the trial conducted in 41 US hospitals that are part of the network of National Institute of Child Health and Human Development (NICHD). The study then compared the outcomes of women whose labor was electively induced at 39 weeks—that is, without a medical reason to do so—with those who were not. Of the 2,875 women induced at 39 weeks, 18.6% ended up having c-sections compared with 22.2% of those who allowed labor to progress naturally. Women who were induced showed lower incidence of postpartum hypertension and infection. There were no statistically significant differences in the health of the newborns.
Not all experts are convinced
William Grobman, the Northwestern University professor of obstetrics and gynecology who led the trial, told Quartz that the decision to measure the impact of induction at 39 weeks was based on studies on neonatal health that show deliveries between 39 and 40 weeks yield the best results for babies’ health.
Grobman sees the study as evidence that induction at the 39th week should be offered as a possibility to first-time mothers with no other complications. This is standard practice at some facilities (including at least one that took part in the trial), particularly when it comes to women who have already given birth vaginally.
The findings of the trial are important toward determining the impact of induction. But there isn’t universal agreement that they are generalizable and that—even if they were—this study should result in including earlier induction as a routine option.
Chitra Akileswaran, a lecturer at Harvard Medical School and co-founder of Cleo, a company that provides health support to working parents, notes that this study seems to move away from the American College of Obstetricians and Gynecologists (ACOG)’s recent push towards low-intervention childbirth.
Akileswaran worries that suggesting earlier induction may be a way of focusing more on medical outcomes rather than what a mother wants. “I have found that more interventions have higher chances of seeming disempowering,” she says, Medical intervention risks setting up expectations that women would have control over the timing of or the levels of their pain, she adds. “Women don’t want to control the process,” she says, “they want to feel that they have agency.”
Emerging from childbirth feeling capable, empowered, and prepared to deal with uncertainty is a better way to be ready for the ups and downs of childcare.
Grobman told Quartz that giving mothers agency through the process was a great concern for the trial, The experience of all of the women in the study was measured twice, immediately after delivery and four to eight weeks after. Women who were induced, he said, reported less pain and a higher sense of agency both right after birth and retrospectively.
The issue of selection bias
Neel Shah, an assistant professor of Obstetrics and Gynecology at Harvard who has done extensive research in medical intervention during childbirth, echoes these concerns. “All studies like this have some limitations. Of the about 23,000 eligible patients in the trial, over 16,000 declined to participate,” he tells Quartz. “This indicates that most women don’t actually want to be induced and that there is selection bias: Those who enrolled might not represent the general population with regard to desire for induction.”
Further, Shah says the outcome with regard to C-sections might not be generalizable. “The reason why inductions are commonly thought to increase the risk of C-section is that they take longer than spontaneous labor,” he says, and “at many hospitals providers and/or patients may be quitting too early.” But doctors participating in the trial knew they were being studied, and might have had the opportunity and staffing resources to wait longer, avoiding C-sections.
Shah also said that the trial doesn’t take into account the cost of added medical intervention or the resources it might require—both of which need to be included in any calculation of the value of the study’s findings.