[Risk factors for stillbirth]

Antenatal fetal death is one of the most devastating complications of pregnancy.

To identify socio-demographic and clinical risk factors for antenatal fetal death.

A case-control study was carried out. Five hundred women were included: Two hundred fifty patients had a stillbirth (cases) and 250 women had a healthy live birth (controls). Stillbirths were considered as antenatal fetal death after 20 weeks of gestation. Seventeen socio-demographic and clinical risk factors for stillbirth were analyzed. Statistical analysis included: Student t test or Mann-Whitney U test for continuous data, and Chi-square or Fisher exact test for categorical variables. Multiple logistic regression analysis (backward stepwise procedure) was used to find significant predictors for stillbirth. Odds ratio (OR) with 95% confidence intervals (95% CI) were calculated. It was set an Alfa level of 0.05.

Six risk factors were significant in the final logistic regression model: Age (OR 1.07, 95% CI 1.03-1.1), smoking habits (OR 9.1, 95% CI 1.07-78.0), placental abruption (OR 51.9, 95% CI 6.8-393.9), cord entanglement (OR 5.0, 95% CI 2.5-9.7), nulliparity (OR 1.3, 95% CI 1.1-1.5) and antenatal care (OR 0.1, 95% CI 0.08-0.4). The whole model had a determination coefficient R2 = 0.234 (p < 0.001).

We developed a predictive model for antepartum fetal death appropriate at our population. The six significant risk factors for stillbirth could be diagnosed early during pregnancy. The antenatal care could be considered the cornerstone for the prevention of antenatal fetal death.