Diet as a counteracting agent of the effect of some well-known risk factors for small for gestational age.

Abstract

OBJECTIVE\nThe aim of this study was to assess whether diet variables can neutralize the risk produced by three well-known risk factors for being small for gestational age: smoking, body mass index (BMI) ˂20 kg/m2, and having a previous preterm/low birth weight (LBW) newborn.\n\n\nMETHODS\nA matched case control study was conducted (518 cases and 518 controls of pregnant women) in Spain. We collected data on demographic characteristics, socioeconomic status, toxic habits, and diet. Dietary intake during pregnancy was assessed using a validated food frequency questionnaire, categorized into quintiles. Adjusted odds ratios (aORs) and their 95% confidence intervals (CI) were estimated by conditional regression logistic models.\n\n\nRESULTS\nWomen who smoked during pregnancy had a 78% increased risk for having an SGA newborn (aOR, 1.78; 95% CI, 1.28-2.74). Lean women (BMI ˂ 20 kg/m2 before pregnancy) augmented the risk 139% (aOR, 2.39; 95% CI, 1.68-3.40), and those with a previous SGA-LBW an increase of 160% (aOR, 2.60; 95% CI, 1.53-4.37). Smoking in women with a fruit intake of ≥421 g/d was not associated with a higher risk for SGA versus non-smoking women with the same fruit intake (aOR, 0.98; 95% CI, 0.41-2.33). A BMI <20 kg/m2 with an intake of ≥33 g/d of legumes did not increase the risk for SGA versus women with a BMI ≥20 kg/m2 with the same legume intake (aOR, 1.35; 95% CI, 0.54-3.37). Diet did not modify the risk by having a previous SGA-LBW newborn.\n\n\nCONCLUSIONS\nSmoking and leanness increased the SGA risk; nevertheless foods such as fruit, fish, and legumes, as well as intake of vitamins D and B3 and ω-3 marine fatty acids, may at least partially counteract this increase.