Associations of maternal height with adverse birth outcomes

  Objective  To investigate associations of maternal height with preterm birth, low birth weight, macrosomia and small gestational age.

  Methods  Complete information on 11 437 pregnant women registered for prenatal care in a provincial level women and children hospital and their babies born between September 2014 and March 2018 were extracted from the information system of Guangdong Provincial Maternal and Child Health Hospital and the pregnant women were divided into three groups according to their height in tertile distribution (≤ 157.0, 157.1 – 161.0, and > 161.0 centimeters cm). Non-conditional multivariate logistic regression model was used to calculate the odds ratios (OR) and their 95% confidence intervals (CI) for maternal height related risk of preterm birth, low birth weight, macrosomia and small gestational age of the newborns.

  Results  The rate of preterm birth, low birth weight, macrosomia and small gestational age were 6.6%, 6.3%, 3.6% and 16.5%, respectively, among all the newborns. After adjustment for potential confounders, logistic regression results showed that maternal height was significantly associated with preterm birth, low birth weight, macrosomia and small gestational age. With every one cm increment in maternal height, the newborn′s risk of low birth weight and small gestational age decreased by 4.7% (odds ratio OR = 0.953, 95% confidence interval 95% CI: 0.939 – 0.968) and 6.8% (OR = 0.932, 95% CI: 0.922 – 0.942), but the risk of macrosomia increased by 11.6% (OR = 1.116, 95% CI: 1.094 – 1.139). Compared with the pregnant women with the body height ≤ 157.0 cm, the risk of having a newborn of preterm birth, lower birth weight and small gestational age reduced by 18.5% (OR = 0.815, 95% CI: 0.677 – 0.980), 40.2% (OR = 0.598, 95% CI: 0.492 – 0.726) and 51.6% (OR = 0.484, 95% CI: 0.426 – 0.551), respectively, and the risk of having a macrosomia increased by 207.0% (OR = 3.070, 95% CI: 2.348 – 4.013) among the pregnant women with the body height > 161.0 cm.

  Conclusion  The pregnant women with shorter stature are at a higher risk of having a preterm birth, low birth weight and small gestational age; while the taller pregnant women are at a higher risk for macrosomia. The results should be concerned in prenatal care to reduce the risk of the adverse birth outcomes.