Rethinking the definition of “term” pregnancy
Obstetricians hear it from their pregnant patients all the time: My back hurts. I’m swollen. I’m exhausted. Get this baby out of me!
“Why do I have to wait for 39 weeks if 37 is good enough?” some have asked Elliott Main, chairman of the ob-gyn department at San Francisco’s California Pacific Medical Center. “Women think it’s fine to deliver at 37 weeks,” he said.
Who can blame them? Technically, a “term pregnancy” is one between 37 and 42 weeks of gestation.
But recent data show that not all of those weeks are equal when it comes to potential complications to the mother and child. Now some doctors and advocacy groups believe the definition is outdated and should change.
As I reported last week, more hospitals are cracking down on elective deliveries – whether by scheduled cesarean sections or labor inductions – between weeks 37 and 39 of pregnancy unless there’s a medical reason.
That’s because babies and moms are at greater risk of complications from elective deliveries during those weeks, ranging from breathing problems to sepsis.
One thing that makes it difficult for hospitals to implement these crackdowns is the definition of “term pregnancy.” Some doctors say they have a hard time selling the concept of patience to their patients, who have gotten used to the notion that giving birth during weeks 37 and 38 is safe.
A survey in the journal Obstetrics & Gynecology shows just how confused women are. Out of 650 women who recently gave birth, 24 percent believed a baby at 34-36 weeks was full term. Nearly 51 percent put full term at 37-38 weeks. One-quarter chose weeks 39 and 40, which are considered optimal weeks to give birth.
John Wachtel, a clinical professor of obstetrics and gynecology at Stanford University Medical School, is among those pushing for a change in the definition.
“Term pregnancy” was defined somewhat arbitrarily, he said, “at a time before ultrasound was available and before we were accurately able to date the pregnancies.”
He pointed to another article, also in Obstetrics & Gynecology, whose authors suggest keeping weeks 37 to 42 labeled as term, but to create subgroups within that category. Weeks 37 and 38 would be called “early term” and weeks 39, 40 and 41 would be “full term.”
Wachtel said that’s a good starting point, but eventually, the goal should be to call only pregnancies during weeks 39, 40 and 41 term, he said.
“If term pregnancy was defined as after 39 weeks, it would really help in trying to change the culture,” he said.