Pregnant women have long been told that when their water breaks, they should be ready to deliver the baby within 24 hours to avoid infection. But a small new study suggests labor may not always need to be induced.
Dutch researchers concluded that in situations where the baby is three to six weeks early or pre-term, and when a woman's amniotic membranes have ruptured before labor has started, it’s best to simply wait and monitor the baby’s progress rather than forcing labor to begin, according to the study published in PLoS Medicine.
There were no fewer fetal blood infections nor breathing problems in babies when labor was induced compared with waiting and monitoring, the researchers found. However, inducing labor did lead to a slight reduction in uterine environment infections, a condition known as chorioamnionitis.
To take a closer look at whether there were any benefits of inducing labor, a team of researchers led by Dr. David van der Ham of the Maastricht University Medical Center randomly assigned 536 women whose water broke at 34 to 37 weeks gestation to be induced or simply to be watched and monitored.
Van der Ham and his colleagues found that among babies born late preterm with pre-labor rupture of the membranes -- water breaking before labor started -- the rate of sepsis and breathing problems did not go up if the babies were allowed to deliver on their own without intervention.
“We conclude that in pregnancies complicated by [preterm pre-labor rupture of the membranes] between 34 and 37 weeks of gestation that the incidence of neonatal sepsis is low,” the researchers wrote. And that means that induction of labor does not substantially improve pregnancy outcomes, they added.
Dr. Christian M. Pettker isn’t convinced that the new data support van der Ham’s conclusions, especially since the researchers also found that induction didn’t lead to an increase in the rate of C-sections.
The study wasn’t large enough to show definitively that waiting and monitoring doesn’t lead to an increased rate of blood infections in newborns, said Pettker, an assistant professor and medical director of the labor and birth section of maternal fetal medicine at the Yale University School of Medicine.
The fact that there was a higher rate of chorioamnionitis among deliveries that weren’t speeded up by induction suggests that the researchers might have seen a higher rate of blood infections if there had been more women in the study, Pettker explained.
That’s because chorioamnionitis raises the baby’s risk of blood infection.
“The study is too small for them to detect if induction is preventing infection in neonates,” Pettker said. “But it appears to be preventing infections before and during labor -- which might translate into a reduced risk of infection in the newborn.”
Ultimately, Pettker reads the data very differently than the Dutch researchers.
“There doesn’t seem to be a lot of risk in doing an induction,” Pettker said. “And there’s a possible benefit. Usually we worry about an increased Cesarean rate [with induction], but in this population there was not an increased risk for Cesarean in the group that was induced.”
Even if a larger study were to confirm this study’s results, Pettker believes that doctors will still offer to induce pregnant patients if their membranes rupture too soon.
“If there does not seem to be a difference between waiting and inducing, it ends up being a discussion between the patient and her providers. Some patients will prefer no intervention in their birth process, while others will feel more comfortable with moving on with things and going forward with an induction.”
First published April 24 2012, 3:33 PM