With a 3-year-old and a 6-year-old at home, Jaclyn McClymonds had at least two good reasons — Joel and Jayla — to want to schedule the delivery of her third child. A charter-school teacher, she was also nervous about juggling a baby plus two little ones and returning to work in time for the school year to begin. At a routine late-pregnancy check-up, she told her doctor she was overwhelmed. “We can schedule an induction at 39 weeks,” he responded.
McClymonds, from Gilbert, Ariz., didn’t know it at the time, but her daughter’s birth on July 6 — and not a day before — reflected a sea change in how her hospital, Banner Desert Medical Center in Mesa, Ariz., addresses the issue of early deliveries. In July, it became one of 19 Banner Healthcare facilities to prohibit scheduled cesarean sections and labor inductions before 39 weeks of pregnancy unless they’re medically necessary.
Historically, a full-term pregnancy has been considered 37 weeks. But that definition has quietly evolved to 39 weeks in light of recent research that babies do lots of critical development during their final weeks in utero.
Now, a trickle of hospitals — estimated to be fewer than 200 of more than 4,500 nationwide — are no longer allowing elective inductions or C-sections before 39 weeks. It’s a pretty significant move considering some experts estimate that 50% of deliveries between 36 and 39 weeks are scheduled.
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More places are bound to follow suit, changing the face of how and when babies are delivered in this country. A toolkit for hospitals designed by the March of Dimes to discourage unnecessary early deliveries has been downloaded thousands of times.
Hospitals in Georgia, Florida and Ohio are discussing the subject, and in Massachusetts, more than 40 birthing hospitals met recently to debate the idea. Some states, including Texas, are passing laws requiring hospitals to develop a plan to limit what’s known as “early-term” deliveries; the Texas legislation goes into effect Sept. 1.
The pressure is only going to intensify come January, when the Joint Commission, which accredits hospitals, is set to require them to meet tougher obstetrics standards. “There is a movement afoot,” says Alan Fleischman, the March of Dimes’ medical director.
But what’s good for babies is not always convenient for their mothers. Moms are losing the convenience of scheduling, and many don’t understand the medical reasons underpinning the shift in policy. Admittedly, it can be confusing. Pregnancy is advertised as a nine-month affair, but if you do the math — in theory, human gestation spans 40 weeks — it’s really more like 10 months. A 2009 study in Obstetrics and Gynecology found that just 25% of moms know full-term pregnancies should last at least 39 weeks.
Doctors, who make money with each new life they usher into the world, aren’t necessarily pleased either. They stand to lose income if they can’t schedule deliveries. Since there’s no predicting when a woman might go into labor, her preferred physician may not be on call when she heads to the hospital.
Meanwhile, other docs — some of whom get a lot of pressure from patients to induce — welcome the guidelines. “They’re so grateful that they don’t have to tell the patient, I won’t do it,” says Ken Welch, chief medical officer at Banner Estrella Medical Center in Phoenix and the health system’s point person on the new policy. “It takes away the adversarial relationship.
“Patients come in and say, I already had two kids born at 37 weeks and they’re just fine,” says Welch, who practiced obstetrics for 25 years. “But we think the data is telling us that to induce electively earlier than 39 weeks is not appropriate. We felt we had to wear our commitment on our sleeve.”
With its new guidelines, Banner, one of the country’s largest non-profit health systems, believes it has the potential to impact the health of the nearly 30,000 babies it delivers each year. It points to a raft of research, including a study published in June in Obstetrics and Gynecology that found that mortality rates are halved by waiting until at least 39 weeks rather than 37 weeks to give birth. Other data have shown that full-term babies — those born at 39 weeks or later — feed better, weigh more and have fewer vision and hearing complications. And imaging has revealed that the brains of babies born after 39 weeks are larger than those of younger infants.
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Last year, 42% of the babies born at Banner hospitals arrived before 39 weeks; the number of elective deliveries wasn’t tracked, though Welch thinks it could be as many as half of early-term births. Of course, not every baby born before 39 weeks is going to have health problems, and that’s part of the public-relations battle that supporters are waging. “We’ve gotten so good at helping babies survive that people think everything’s going to be fine,” says Welch. “We are victims of our own success.”
This summer, the March of Dimes unveiled its own 39-week campaign, taking out full-page ads in women’s magazines to make the case that “Healthy Babies Are Worth the Wait.”
“Most pregnant women when given a choice usually schedule their delivery date based on convenience,” says Eugene Toy, academic chief of OB/GYN at St. Joseph Medical Center, which has participated in a March of Dimes pilot project aimed at staving off unnecessarily early deliveries in five hospitals in each of the five states with the most births — New York, California, Illinois, Florida and Texas. “Sometimes it’s even numerology. One patient chose her delivery date based on an astrological sign.
“I tell patients it’s like baking a cake,” says Toy. “Even if you have hungry guests, you don’t rush the cake out of the oven before it’s ready.”
Bonnie Rochman is a reporter at TIME. Find her on Twitter at @brochman. You can also continue the discussion on TIME‘s Facebook page and on Twitter at @TIME.