[Incidence and risk factors of the hushed weight to the being born on population once was attended in the Peru's hospitals of the health ministry].

OBJECTIVE: Knowing incidence and risk factors of hushed weight to the being born on population that went once was attended in the Peru's hospitals of Health Ministry.

MATERIAL AND METHODS: I study prospective, epidemiologic, of cases and controls. Compared with 14846 controls of 2500. Were examined to 3999 g total of 7423 alive newborns with younger weight to 2500 only pregnancy, tumors g. in 29 hospitals of Health Ministry of the Peru in the year 2007. Selected candidates at random. Came true analysis bivariado and intervening multivariado logistic regression, utilizing OR with intervals trustworthy to the 95%. Data base was utilized of the System Informatics Perinatal.

RESULTS: He values it of hushed- weight incidence to the being born was 8.24 x 100 born living persons, with significant differences among geographic regions. The risk factors attended: Illness hipertensiva of the pregnancy (OR = 4.37), hemorrhage of the third trimester (OR = 4.28), chronic illness (OR = 2.92), premature rupture membrane (OR = 2.85), mother with bajo peso al nacer (OR = 2.27), antecedent of bajo peso al nacer (OR=1.66), absence or prenatal control inadequate (OR = 1.91), illiteracy or primary education (OR = 1.48), region saws or jungle (OR = 1.36), he carves maternal minor of 1.50 m (OR = 1.15) and interval younger two-years ntergenésicos (OR = 1.13). These risk factors have 68% of value predictive. He intends additive scale to identify women with bigger risk in order to bajo peso al nacer.

CONCLUSION: He finds bajo peso al nacer'S incidence in hospitals of Health Ministry of the Peru in the average Latin-American and maternal nutritional, absence or prenatal control are associated to the deficient status inadequate and maternal pathology.