Areal, AMoreira, MNunes, SFaustino, MACardoso, LSá, C2013-08-302013-08-302008Acta obstet Ginecol Port 2008;2(2):72-79http://hdl.handle.net/10400.23/497Aim and Objective: During the past three decades, group B Streptococcus (GBS) neonatal infection has been the subject of little research. The aim of this study was to evaluate the association between maternal risk factors, as established by the Center for Disease Control and Prevention (CDC), and maternal colonization. We also analysed the association between risk factors present in newborns and early-onset GBS disease. Study design: Cross-sectional study. Population: All pregnant women admitted for delivery in our institution and their newborns, between 1st February and 31st July 2005. Methods: Maternal and neonatal characteristics were collected from hospital clinical data, including information on risk factors established by the CDC. Descriptive statistics was used to characterize the study sample. Qui-square and Mantel-haenszel tests were applied to compare proportions and to measure the strength of associations, respectively, setting significance at p < 0,05. Results: In this sample only 47% of women were screened for GBS colonization in suitable time and 34,9% of these women were colonized. The incidence of early neonatal infection by SGB was 9/1000 neonates. Significant associations between GBS maternal colonization ant the following parameters were observed: maternal age [p=0,012; OR=1,659 (IC a 95%, 1,218-2,260)], gestational age at labour [p=0,001; OR= 2,621 (IC a 95%, 1,641- 4,188)], and urinary GBS infection during pregnancy (p<0,001). Maternal colonization occurred in women without CDC defined risk factors. Early neonatal infection by SGB was strongly associated with unscreened women (p=0,014). Conclusion: In this study, maternal GBS colonization occurred in the absence of CDC defined risk factors and varied according to maternal age and gestational week. Neonatal GBS infection was more frequent in unscreened women.porComplicações Infecciosas na GravidezInfecções EstreptocócicasStreptococcus agalactiaeDeterminantes da colonização materna e da infecção neonatal por Streptococcus do grupo Bmaternal colonization and neonatal infection with group B Streptococcusjournal article