Incidence and main causes of severe maternal morbidity in São Luís, Maranhão, Brazil: a longitudinal study.

CONTEXT AND OBJECTIVE Evaluation of severe maternal morbidity has been used in monitoring of maternal health. The objective of this study was to estimate its incidence and main causes in São Luís, Maranhão, Brazil. DESIGN AND SETTING Prospective longitudinal study, carried out in two public high-risk maternity hospitals and two public intensive care units (ICUs) for referral of obstetric cases from the municipality. METHODS Between March 1, 2009, and February 28,2010, all cases of severe maternal morbidity according to the Mantel and Waterstone criteria were identified. The sociodemographic and healthcare characteristics of the extremely severe cases were compared with the less severe cases, using the Fisher, χ(2), Student t and Mann-Whitney tests, with a significance level of < 0.05. RESULTS 127 cases of severe maternal morbidity were identified among 8,493 deliveries, i.e. an incidence of 15.0/1000 deliveries. Out of 122 cases interviewed, 121 cases were within the Waterstone criteria and 29 were within the Mantel criteria, corresponding to incidences of 14.1/1000 and 3.4/1000 deliveries, respectively. These rates were lower than those described in the literature, possibly due to case loss. The main causes were hypertension during pregnancy, which was more frequent in less severe cases (P = 0.001) and obstetric hemorrhage, which was more common among extremely severe cases (P = 0.01). CONCLUSIONS Direct obstetric disorders were the main causes of severe maternal morbidity in São Luís, Maranhão. Investigation and monitoring of severe morbidity may contribute towards improving obstetric care in the municipality.