Birth weight patterns by gestational age in Brazil

Abstract

Background and objectives. We present an updated birth weight-for-gestational-age portrait, based on nearly 8 million observations of an ethnic-mixed population. It comprises the first comprehensive charts with Brazilian data. This contribution intends to assist clinicians in classifying fetal growth, to provide a reference for investigations of predictors and to show the consequences of small and large patterns for gestational age delivery. Most of the reference data for assessing birth weight for gestational age deal with insufficient sample size, especially at low gestational age. Population-based studies with considerably large sample size refer to data collected more than 15 years ago. Methods. We accomplished a population-based study on births in all the Brazilian states from 2003 to 2005. Results were based on 7,993,166 singletons. We constructed the 3 rd , 5 th , 10 th , 25 th , 50 th , 90 th , 95 th and 97 th smoothed percentiles curves and gender-specific tables from 22 to 43 completed weeks. Results. The resulting tables and graphical representation provide a gender-specific reference to access the birth weights distribution according to the gestational age in the Brazilian population. Conclusions. This is the first population-based reference constructed on a developing country data. These charts could provide an important tool to improve clinical assessment of growth in newborns.

IncIdence of congenItal SyphIlIS In a MetropolItan regIon of rIo de JaneIro State: SocIal InequalItIeS

“…When both were absent, the evaluation of the newborn by Capurro method (10) or Ballard (11) were applied, and registered by the pediatrician. To assess suitability of the weight to the gestational age, the standards established for Brazilians neonates were used (12) . The data were processed and analyzed by SPSS® statistical software, version 17.…”

Birth weight classification in gestational diabetes: is there an ideal chart?

“…Rates of male SGA newborns were similar for the two charts based on national registries, even considering that the first one was built upon data collected more than 10 years ago, and grouped gestational age at three-week intervals 8 . In female newborns, an unexpectedly higher rate of SGA was found when applying the contemporary curve, SINASC-2012, compared to the late Pedreira, a finding we could not thoroughly clarify herein because we did not adjust frequencies to potential confounders like smoking or hypertension in pregnancy.…”

“…The four charts we compared were: 1) Alexander et al 7 , an American chart that is reference in our hospital, classifies babies according to gestational age and is adjusted for sex only for the 10th percentile; 2) Pedreira et al 8 , which was built based on 7,993,166 certificates of birth weight from Brazilian babies delivered from 2003 to 2005, with data plotted for 3-week intervals of gestational age, stratified by sex, with interpolation of calculated birth weights for the gestational ages in the intervals; 3) INTERGROWTH-21st 6 , intended to be the adopted by the World Health Organization; 4) SINASC-2012 chart.…”

“…More than 100 curves relating birth weight and gestational age are available, most of them built upon regional or local registries 6 . The American Alexander's chart is our reference curve 7 , although one based on a large nationwide registry was suggested in the past 8 . In an attempt to unify newborn birth weight classification worldwide, a new chart was recently proposed 6 .…”

Fetal Growth Pattern and Prediction of Low Birth Weight in Gastroschisis

“…Low birth weight was considered when an infant's weight was below the 10th gender-specific percentile according to our population [14]. …”