Dose-response relationships of maternal height and weight with risk of low birthweight neonates: a meta-analysis

The development of novel methods to identify pregnant women at increased risk of low birthweight neonates before delivery is required to improve pre- and periconceptional strategies to reduce the prevalence of low birthweight neonates. A dose-response meta-analysis was performed to examine the adjusted relationships of maternal height and weight with risk of low birthweight neonates.

PubMed (Medline), CINAHL, PsycINFO, Wiley Online Library, ProQuest, Web of Science, Google Scholar, and Sage Journals Online were searched. There were no restrictions regarding publication date. English-language cohort studies involving singleton births that provided adjusted relative risks or Odds Ratios for low birthweight neonates at two or more values of maternal height or weight compared to the reference and numbers of low birthweight neonates and numbers of normal birthweight neonates in these values and the reference are included.

From the five finally eligible studies, four good-quality studies evaluating the relationship of maternal height with risk of low birthweight neonates and three good-quality studies evaluating the relationship of maternal weight with risk of low birthweight neonates were extracted. Both of these relationships were non-linear rather than linear (P values for non-linearity <0.05). Based on the non-linear dose-response model, maternal height limited to below 160 cm and maternal weight with no restrictions regarding the range were significantly and negatively related to risk of low birthweight neonates.

Risk of low birthweight neonates may decrease with increasing maternal height from below 160 cm to 160 cm and by increasing maternal weight regardless of above or below 55 kg.