Study of maternal risk factors associated with early-onset neonatal sepsis in a tertiary hospital of the Brazilian Amazonia

PURPOSE: to identify the main maternal risk factors involved in early-onset neonatal sepsis, evaluating the risk associations between bacterial vaginosis and isolated microorganisms found in the maternal urine culture and in the newborn blood culture in the delivery room. METHODS: randomized longitudinal cohort study involving 302 mothers and their newborns. All neonates were followed up for seven days in order to diagnose sepsis. RESULTS: the outcomes were the following: 16 (5.3%) early-onset neonatal sepsis cases (incidence of 53 cases per 1,000 live births). The average number of prenatal appointments with a doctor was 5.2 (SD=1.8). The number of women with prenatal follow-up was 269 (89.1%), but only 117 (43.4%) of them went to six or more medical appointments, 90 (29.8%) had premature rupture of membranes before delivery, but only 22 (7.3%) had it for more than 18 hours. A total of 123 women (40.7%) complained of vaginal discharge, but only 47 (15.6%) of them had bacterial vaginosis, 92 (30.4%) complained of urinary infection, but only 23 (7.6%) of them had bacteriuria, two (0.7%) had fever at home, 122 (40.4%) received intra-partum antibiotic prophylaxis, 40 (13.2%) had premature delivery and 37 (12.3%) had low-birth-weight babies. Gestational age was a signifi cant risk factor (RR=92.9; IC 95%: 12.6-684.7), as well as the number of prenatal appointments (RR=10,8; IC 95%: 1,4-80,8), fever (RR=10,0; IC 95%: 2,3-43,5), low-birth-weight (RR=21,5; IC 95%: 7,3-63,2) and early neonatal death (RR=89,4; IC 95%: 11,16-720,6). A signifi cant difference of 5% was found in the comparison of the averages of lower number of prenatal appointments, prematurity and lower birth weight. CONCLUSIONS: the major microorganism isolated in the newborns' blood culture was the Streptococcus agalactiae. Prematurity, lack of prenatal follow up and low birth weight were the risk factors more associated with early neonatal sepsis.