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Growth Curve

The inexact science of raising kids

Laura Sanders
Growth Curve

Induced labor doesn’t necessarily kick off cascade of interventions

pregnant woman in hospital

One argument against hospital births suggests that one medical intervention raises the risk of another. But a large analysis of clinical trials finds that jump-starting labor actually leads to fewer C-sections.

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Pregnant women live in a constant state of worry. And for good reason. Mothers-to-be are bombarded with a constant stream of advice throughout their pregnancies. Eat lots of fish, but not too much, and definitely not the wrong kinds. Don’t use that zit cream, or hair dye or nail polish. Don’t stand too close to the microwave and keep that cell phone away from the belly.

One of the scariest parts of pregnancy comes at the very end. Pregnant women are often terrified of an overly medicalized birth that spirals out of control. A pervasive argument made against hospital births is that one intervention during labor ups the risk of another. A single, seemingly innocuous medical procedure can kick off a chain of events that leads to another one, which leads to another one, until the baby is inevitably delivered via cesarean section, the reasoning goes. Avoiding this snowball effect, referred to as the “cascade of interventions,” is one of the main reasons women are increasingly turning to midwives or giving birth at home, a practice that carries its own substantial risks.

But a certain link in this chain of events appears to be broken, a new review of the literature suggests. Women who had their labor artificially kick-started with drugs were actually less likely to give birth via a C-section than women whose labor was allowed to proceed at its own pace, suggests a new study, which analyzed the outcomes of 157 randomized controlled clinical trials.

When a pregnant woman or her fetus shows signs of distress, or the pregnancy has continued past 42 weeks, doctors can use drugs to artificially create contractions and ready the cervix for delivery. Currently, labor is induced in about one of five births. Many people believed that these inductions act as catalysts that kick off an inevitable series of medical procedures that culminate in a C-section.

Not so, shows the new analysis, published April 28 in the Canadian Medical Association Journal. When the authors analyzed the results from the 157 studies, all of which randomly assigned some women to be induced while others were not, the trend was clear: Women who had reached the end of their pregnancy or passed it who had their labor induced were about 12 percent less likely to wind up with a C-section delivery than women who weren’t induced. This idea is not new: Other single clinical trials have turned up similar results. Yet the myth persists on many websites that advocate natural births, and even in textbooks and clinical guidelines, the authors write.

The data say nothing about the other potential links in the cascade of interventions, which could easily be real. And the results are based on averages. Any individual woman’s medical needs and outcome are unique to her. And of course, any woman in labor has the right to guide her own medical decisions.

One of the scariest things about being in labor is the vulnerability. The loss of control, whether it’s to doctors or to a body that’s intent on doing its thing, is terrifying, especially when the outcome involves a tiny new baby. But when faced with frightening situations, it might help to come armed with as much knowledge as possible. And that’s why these sorts of studies, especially those that run counter to the prevailing ideas, are worth talking about.

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