American Journal of Clinical Nutrition, Vol 33, 2311-2317, Copyright © 1980 by The American Society for Clinical Nutrition, Inc

ORIGINAL RESEARCH COMMUNICATIONS

Intrauterine growth: correlation of infant birth weight and maternal postpartum weight

B Luke and RH Petrie

The influence of increasing maternal "nutrient pool," as postpartum weight for height, on infant birth weight was investigated. Two hundred ninety-four uncomplicated, term pregnancies were studied. Each gravida was categorized by height and postpartum weight as underweight (group I, 70.0 to 119.9%), normal weight (group II, 120.0 to 159.9%), or overweight (group III, 160.0 to 209.9%). Within group I, mean infant birth weights increased 214 g with each 10% increase in maternal postpartum weight (correlation coefficient = +0.936). In group II, the same increase in maternal postpartum weight paralleled an increase of 41.9 g in infant birth weight (correlation coefficient = +0.467). In group III, a negative relationship was shown between increasing maternal postpartum weight and birth weight (correlation coefficient = - 0.130). With each increase of 10% in maternal postpartum weight there was a decrease of 29.8 g in infant birth weight. Maternal metabolic needs must take preference over fetal requirements at the extremes of the maternal nutrient pool, resulting in some degree of intrauterine growth retardation. Only when the maternal nutrient pool is brought into the normal range (group II) can optimal intrauterine growth be realized.