Search Here

For years, doctors and expectant mothers have understood that a full term pregnancy is anywhere from week 37 to week 42. Infants born during these weeks are considered to be fully developed and are at a reduced risk of future health complications. Several studies conducted in the past have found evidence that giving birth before preterm could be extremely detrimental to the infant's physical and cognitive development. Due to the risks involved with giving birth preterm, the American College of Obstetricians and Gynecologists have decided to reclassify the terms associated with pregnancy. According to the doctors, the end of the third trimester needs to be categorized into four groups, which are early term, full term, late term and postterm.

Under the new guidelines, the doctors stated that early term is now between week 37 and 38. Week 37 and 38 used to be considered a safe time for an infant to be born, but due to recent studies and mounting evidence, doctors believe that letting the infant sit in the womb a week longer could result in positive outcomes. One study found that infants born during weeks 37 to 38 were more likely to need time in the NICU where they might receive mechanical ventilation or IV fluids. In order to reduce those risks, the new definition states that a full term pregnancy is from week 39 to 40. Week 41 is now understood as late term and anything after week 42 is postterm.  

The experts hope that the new guidelines will encourage women to carry out pregnancies longer. Based on statistics, the number of babies born during week 37 or week 38 has increased from 17 percent in 1983 to 27 percent in 2009 due to the fact that mothers have been asking for induction and scheduled Cesarean sections. Since preterm pregnancies can lead to more complications and inevitably more medical bills, these new definitions are set to dissuade mothers from scheduling their births too early.

"Language and labels matter," explained Jeffrey Ecker from the Massachusetts General Hospital.

The new definitions were published in the journal, Obstetrics & Gynecology.