Diet in pregnancy and risk of small for gestational age birth: results from a retrospective case-control study in Italy

This study aims to analyse the association between selected dietary indicators during pregnancy and the risk of small for gestational age (SGA) births in a South European population. This is a case-control study. Cases were 555 women who delivered SGA babies at the Luigi Mangiagalli Clinic of Milan and the Obstetric and Gynecology Clinic of the University of Verona. The controls were women who gave birth at term (≥37 weeks of gestation) to healthy infants with normal weight in the same clinics. Dietary information was collected with a food frequency questionnaire. Women with SGA babies reported a more frequent consumption of meat and olive oil, and a less frequent consumption of fish and eggs. Women with high consumption of olive oil had an increased risk of delivering an SGA baby [odds ratio (OR) 1.6, 95% confidence interval (CI) 1.0-2.5]. The multivariate OR for high meat consumption was 1.4 (95% CI 1.1-1.9); for fish 0.8 (95% CI 0.6-1.0, χ² for trend 4.0, P = 0.045 ) and for egg 0.7 (95% CI 0.5-0.9). After allowing for factors generally known to be associated with SGA, we have shown that eating more fish and eggs, and less meat and possibly olive oil, are associated with a lower risk of delivering an SGA baby.