Prevalence and risk factors for low birth weight in Ardabil, Iran.

Introduction Low birth weight (LBW) is the most common cause of neonatal death in developing countries. The objective of our study was to determine the prevalence and risk factors associated with low birth weight in Ardabil, Iranfrom 2010 to 2011.Methods In a case–control study all live newborns were weighted without clothing using a standard calibrated scale. Gestational age was calculated using either the first day of the last normal menstrual period or estimated by obstetric sonography. 358 neonates with birth weight of less than 2500 g were considered as case and 705 normal weight neonates as control groups. Data were collected through a self-designed questionnaire from review of prenatal and hospital delivery records. Kruskal –wallis, chi-square, and logistic regression were applied to analyze data using SPSS version 16.Results Incidence of LBW was 6.3% and among these, 84.2% were preterm and 15.8% had intrauterine growth retardation. Hypertension (OR:8.64, CI: 2.63-28.31), multiple pregnancy (OR: 7.62, CI:3.09-13.32), leakage (OR:4.46, CI: 2.11-9.42), Oligohydramnios(OR:4.28, CI:1.90-9.76),history of preterm birth (OR:2.84, CI: 1.20-6.71), bleeding or spotting during pregnancy (OR:2.36,CI:1.41-3.95) were determined as important risk factors for preterm LBW. Risk of low birth weight in term infants increased by multiple pregnancy (OR:3.77, CI: 1.41-10.0), bleeding and spotting(OR:2.23, CI:1.22- 4.07),and urinary tract infection in weeks 26-30 of pregnancy (OR:2.42, CI :1.11-5.26).Conclusion Delivering quality health care for all pregnant women and early diagnosis and control of hypertension, urinary tract infection, and bleeding or spotting and leakage during pregnancy may significantly reduce the rate of low birth weight and improve public health in this area.