Trends in prenatal care use and low birthweight in southeast Brazil.
OBJECTIVE
We investigated trends in prenatal care use and its association with low birthweight in a developing country.


METHODS
We examined data from 2 southeast Brazilian cohort surveys, 1 conducted in 1978-1979 and the other in 1994.


RESULTS
Socioeconomic inequalities in prenatal care use increased during the 15-year period of 1979-1994. Although prenatal care use increases paralleled increases in low birthweight rate during this period, having no prenatal care was associated with higher risk of low birthweight in both surveys. Inadequate prenatal care use was also associated with higher risk of low birthweight in 1978-1979 only.


CONCLUSIONS
Increasing low birthweight rates among women who adequately used prenatal care may be causing a bias by reducing the estimates of the effect of inadequate prenatal care use on low birthweight rates.
Goldani
Marcelo Z
MZ
Department of Paediatrics and Puericulture, Faculty of Medicine, Federal University of Rio Grande do Sul, Brazil. mgoldani@hcpa.ufrgs.br
Barbieri
Marco A
MA
Silva
Antonio A M
AA
Bettiol
Heloisa
H
D015982:Bias; D001723:Birth Rate / Q000639:trends; D001938:Brazil / Q000453:epidemiology; D015331:Cohort Studies; D003906:Developing Countries; D004522:Educational Status; D005260:Female; D005865:Gestational Age; D019538:Health Care Surveys; D006771:Hospitals, Maternity; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D017533:Marital Status; D008423:Maternal Age; D010298:Parity; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D011295:Prenatal Care / Q000592:standards / Q000706:statistics & numerical data / Q000639:trends*; D016016:Proportional Hazards Models; D011787:Quality of Health Care; D012307:Risk Factors; D012959:Socioeconomic Factors