Prevalence, risk factors, maternal and fetal morbidity and mortality of intrauterine growth restriction and small-for-gestational age

Objectives. - To assess the prevalence of fetal growth restriction (FGR) and small for gestational age (SGA) in France and other populations, the risk factors associated with SGA and its impact on fetal well-being and obstetrical outcome. Methods. - A critical review of studies identified from searches of PubMed and the Cochrane libraries using the following keywords "intra-uterine growth retardation", "intra-uterine growth restriction", "small for gestational age", "epidemiology", "risk factors", "pregnancy outcome", "maternal morbidity", "perinatal death". Results. - Studies of FGR use multiple definitions, both with respect to cutoffs for defining restricted growth as well as growth norms; however the most common definition for epidemiological research was SGA using a birthweight less than the 10th percentile. Following this definition, SGA births accounted for 8.9% of all live births in 2010 in France. Major risk factors identified in the literature were previous SGA birth (4 fold increase in risk) (LE2), diabetes and vascular diseases (5 fold) (LE3), chronic hypertension (2 fold) (LE2), preeclampsia (5 to 12 fold according to severity) (LE2), pregnancy induced hypertension (2 fold) (LE2), smoking (2-3 fold) (LE2), drug and alcohol use (2-4 fold) (LE2), maternal age over 35 (3 fold) (LE2) and ethnic origin (2-3 fold for African-American or Asian origins) (LE2). Other risk factors with adjusted odds ratios around 1.5 were primiparity (LE2), multiple pregnancy (but only starting at 30 weeks of gestation) (LE2), socioeconomic disadvantage (LE2) and body mass index (BMI < 18.5 kg/m(2)) (LE2) SGA is associated with a four-fold increased risk of stillbirth (LE2) as well as higher rates of cesarean and induced labor before 37 weeks. Conclusions. - FGR is a complication of pregnancy with adverse consequences for fetal wellbeing. Sociodemographic and clinical risk factors can help to identify pregnant women at risk for this complication. (C) 2013 Elsevier Masson SAS. All rights reserved.