This cross-sectional study was carried out to capture possible maternal factors affecting newborns' anthropometric measurements. Data were collected from eight public health centres and referral university hospital records in Tabriz and Heriss districts, north-west Iran, for 807 mother-neonate pairs delivering live singleton births and their offspring during the two years up to August 2014. The incidence of low birth weight (LBW) was 5.1%. A close correlation was found between maternal anthropometry and birth order with neonatal anthropometric data. Birth order and maternal height and body mass index (BMI) positively affected neonates' birth size (weight, length and head circumference). The rate of LBW was significantly higher for older (≥35 years), taller (≥170 cm), underweight (BMI<18.5) and non-iron-taking women and in the first-born babies. The odds of having LBW newborns in older, taller, underweight, obese and irregular iron-taking women were 3.82, 4.00, 9.07, 3.50 and 2.50 times those of mid-age group, middle-height, overweight and regular iron-taking women, respectively. First-born newborns were 5.97 times more likely to be LBW compared with second-birth neonates. The results indicate that maternal anthropometric indices, age, iron intake and birth order influence the risk of LBW in newborns.