Risk factors for pre-eclampsia in a large cohort of Latin American and Caribbean women.

OBJECTIVE: To study risk factors for pre-eclampsia in a large cohort of Latin American and Caribbean women.

DESIGN: Retrospective cross-sectional study from the Perinatal Information System, the database of the Latin American Center for Perinatology and Human Development, Montevideo, Uruguay.

SETTING: Latin America and the Caribbean, 1985-1997. Population 878,680 pregnancies at 700 hospitals; of these 42,530 were complicated by pre-eclampsia and 1,872 by eclampsia.

MAIN OUTCOME MEASURES: Crude and adjusted relative risks (RR) of risk factors for pre-eclampsia. Adjusted relative risks were obtained after adjustment for potential confounding factors through multiple logistic regression models based on the method of generalised estimating equations.

RESULTS: The following risk factors were significantly associated with increased risk of pre-eclampsia: nulliparity (RR 2 x 38; 95% CI 2 x 28-2 x 49); multiple pregnancy (RR 2 x 10; 95% CI 1 x 90-2 x 32); history of chronic hypertension (RR 1 x 99; 95% CI 1 x 78-2 x 22); gestational diabetes mellitus (RR 1 x 93; 95% CI 1 x 66-2 x 25); maternal age > or = 35 years (RR 1 x 67; 95% CI 1 x 58-1 x 77); fetal malformation (RR 1 x 26; 95% CI 1 x 16-1 x 37); and mother not living with infant's father (RR 1 x 21; 95% CI 1 x 15-1 x 26). Pre-eclampsia risk increased according to pre-pregnancy body mass index (BMI). In comparison with women with a normal pre-pregnancy BMI (19 x 8 to 26 x 0), the RR estimates were 1 x 57 (95% CI 1 x 49-1 x 64) and 2 x 81 95% CI 2 x 69-2 x 94), respectively, for overweight women (pre-pregnancy BMI = 26 x 1 to 29 x 0) and obese women (pre-pregnancy BMI > 29 x 0). Cigarette smoking during pregnancy and a pre-pregnancy BMI < 19 x 8 were significant protective factors against the development of pre-eclampsia. The pattern of risk factors among nulliparous and multiparous women was quite similar.

CONCLUSIONS: Risk factors for pre-eclampsia observed among Latin American and Caribbean women are similar to those found among North American and European women.