Babies Born Even Slightly Early May Lag Behind
Women urged to rethink early elective C-sections, inductions unless medically needed
By Kathleen Doheny
TUESDAY, April 16 (HealthDay News) -- Many women choose to have labor induced or to have an elective Cesarean delivery before the full term of their pregnancy is up, but a new study suggests their child's development may suffer if they are born even a little early.
A term of 37 to 41 weeks is considered ''normal,'' but the new research finds birth at 39 to 41 weeks provides more developmental advantages compared to birth at 37 to 38 weeks.
"If the pregnancy is going well, it would be better to avoid doing elective C-sections early in the full-term window," said study author Dr. Betsy Lozoff, a professor of pediatrics and communicable diseases at the University of Michigan.
She and her colleagues tested 1,562 infants when they were 1 year old, then looked back to see at what week of term they were delivered. The babies were all born in Chile and all were delivered within the full-term window. Their average birth weight was 6.6 pounds.
For every additional week in the womb, however, the mental developmental test scored increased very slightly, by 0.8. The psychomotor scores -- which relate to body movement and coordination -- increased by 1.4 points for every additional week. This held after the researchers accounted for birth weight, gender, socioeconomic status and home environment.
The study is published online April 15 and in the May print issue of the journal Pediatrics.
The trends of early induction and early C-sections have increased to 40 percent of all births, according to the researchers. Because of how common they are, the study authors wanted to focus on the effects of brain development with early deliveries. According to the U.S. Centers for Disease Control and Prevention, the C-section rate reached 32 percent in 2007 in the United States.
The differences found in testing, on an individual level, were small, Lozoff said. The study reported average differences, so not all children born early were affected.
However, on a societal level, it could be very important, she said. "To give some reference point, the differences observed in this study are as large as those observed with low-level lead exposure." Exposure to lead has long been linked with developmental lags in children.