Smoking during Pregnancy: A Risk Factor for Stunting and Anemia in Infancy

Abstract

Background: The co-occurrence of smoking, stunting, anaemia and poverty represent multiple biological and psychosocial risks that increase unjust and unfair inequalities since early infancy. Smoking during pregnancy not only increases risk of intrauterine growth retardation (IUGR) and preterm birth, also impacts negatively on growth and child development. Study design and subjects: Study population came from a cross-sectional, national, representative survey conducted in Uruguay (2011) involving 2,994 infants <24 months to study stunting and overweight and a sample of 756 infants 6-24 months to investigate anaemia. Birth weight, birth length and gestational age were taken from health records. Measurements of current weight, length and head circumference were collected by appropriately trained nutritionists following WHO anthropometry recommendations. Binary logistic regression was carried out to estimate the probability of stunting and anaemia in offspring of mother who continuing smoking during pregnancy controlled for intrauterine growth retardation (IUGR) and for maternal and social variables. Major findings: Smoking remains prevalent in younger and less educated women in Uruguay; 23.2% of women smoke and 12.6% smoke while pregnant. Stunting prevalence was almost double (16.8% vs 10.4% P<0.001) and anaemia prevalence was higher: 47.1% compared 29.7% among non-smokers (P=0.002). The results indicate that intrauterine smoke exposure increased chance of intrauterine growth retardation OR:3.0(1.7-5.2); stunting OR: 1.5(1.1-2.1) and anaemia OR:1.9(1.1-3.0). Conclusions: Our results highlight the association between smoking exposure in utero with stunting and anaemia particularly in infants living in a poverty context. Consequently efforts to prevent smoking should be a cornerstone in promoting healthy child growth and development.