title: [Perinatal factors related to the morbidity and mortality of newborns in nine neonatal care units in the city of São Paulo].
abstract: This study was carried out in nine hospitals in the city of São Paulo, in 1991 (between July 1 and November 30), when 10,235 live children were born. The aim of this study was to analyze the characteristics of the 1975 pathologic newborn (PNB) who were put into those neonatal care units (NCU) of the hospitals; besides that, the most common morbidity conditions, breast feeding prevalent and therapies were studied. It was calculated the odds ratio, its confidence interval and the c(2) test in order to evaluate the association between the variables and the death of the PNB. The results have demonstrated that the low weight PNB lethality (especially those with weight <1500 g) was higher than those PNB whose weight was > or = 2500 g. The lethality for both premature PNB and small for gestational age PNB was higher than the other categories of babies. The PNB with hypoxia until the 5th minute had the worst prognostic: their lethality was 10 times higher than the other category. The PNB who had Apgar < or =7 until the 5th minute had twice as much lethality when compared with PNB who had Apgar < or =7 just until the 1st minute. Conventional therapies have been used and only 25.4% have received breast feeding. Several risk factors (maternal, delivery, newborn) were associated with the PNB mortality, as well as most of the morbidity conditions. Those factors reflect the perinatal assistance in our environment.