U.S. Birth Weights Dropping Due to Earlier Delivery February 11, 2020
Written by MSDC Staff
New analysis of CDC data shows that the average birth weight of U.S. babies has actually dropped in the last few decades, but not enough to cause a public health concern.
Between 1990 and 2013, the average weight of a newborn baby dropped 2.4 ounces - from 7.31 pounds to 7.16 pounds. This is based on analysis done by researchers from the University of Colorado from CDC data (see WashPost story here).
During the same time period, the percentage that a birth would occur at 40 weeks dropped (29% -> 18%) while the percentage chance that a birth would occur in weeks 37-39 increased (38% -> 49%). Researchers point to the increase in Caesarean sections and induce labor during this period for the shift in birth weight and earlier deliveries. However, the 7.16 pound average birth weight is well above the medically accepted boundary of 5 pounds, 8 ounces for low birth rate.
While c-section births are safe medical procedures, the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM) recognize that the rise in c-section rates may have external factors. Their 2014 Obstetric Care Consensus (reaffirmed in 2019) points to different strategies to reduce unnecessary c-sections.
Between 1990 and 2013, the average weight of a newborn baby dropped 2.4 ounces - from 7.31 pounds to 7.16 pounds. This is based on analysis done by researchers from the University of Colorado from CDC data (see WashPost story here).
During the same time period, the percentage that a birth would occur at 40 weeks dropped (29% -> 18%) while the percentage chance that a birth would occur in weeks 37-39 increased (38% -> 49%). Researchers point to the increase in Caesarean sections and induce labor during this period for the shift in birth weight and earlier deliveries. However, the 7.16 pound average birth weight is well above the medically accepted boundary of 5 pounds, 8 ounces for low birth rate.
While c-section births are safe medical procedures, the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM) recognize that the rise in c-section rates may have external factors. Their 2014 Obstetric Care Consensus (reaffirmed in 2019) points to different strategies to reduce unnecessary c-sections.