Excessive gestational weight gain predicts large for gestational age neonates independent of maternal body mass index

J Matern Fetal Neonatal Med. 2012 May;25(5):538-42. doi: 10.3109/14767058.2011.638953. Epub 2011 Dec 21.


Objective: To determine the effects of maternal pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) on large-for-gestational-age (LGA) birth weight (≥90th % ile).

Methods: We examined 4321 mother-infant pairs from the Ottawa and Kingston (OaK) birth cohort. Multivariate logistic regression (controlling for gestational and maternal age, pre-pregnancy weight, parity, smoking) were performed and odds ratios (ORs) calculated.

Results: Prior to pregnancy, a total of 23.7% of women were overweight and 16.2% obese. Only 29.3% of women met GWG targets recommended by the Institute of Medicine (IOM), whereas 57.7% exceeded the guidelines. Adjusting for smoking, parity, age, maternal height, and achieving the IOM's recommended GWG, overweight (OR 1.99; 95%CI 1.17-3.37) or obese (OR 2.64; 95% CI 1.59-4.39) pre-pregnancy was associated with a higher rate of LGA compared to women with normal BMI. In the same model, exceeding GWG guidelines was associated with higher rates of LGA (OR 2.86; 95% CI 2.09-3.92), as was parity (OR 1.49; 95% CI 1.22-1.82). Smoking (OR 0.53; 95%CI 0.35-0.79) was associated with decreased rates of LGA. The adjusted association with LGA was also estimated for women who exceeded the GWG guidelines and were overweight (OR 3.59; 95% CI 2.60-4.95) or obese (OR 6.71; 95% CI 4.83-9.31).

Conclusion: Pregravid overweight or obesity and gaining in excess of the IOM 2009 GWG guidelines strongly increase a woman's chance of having a larger baby. Lifestyle interventions that aim to optimize GWG by incorporating healthy eating and exercise strategies during pregnancy should be investigated to determine their effects on LGA neonates and down-stream child obesity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Body Mass Index*
  • Cohort Studies
  • Female
  • Fetal Macrosomia / etiology*
  • Guidelines as Topic
  • Humans
  • Infant, Newborn
  • Logistic Models
  • Middle Aged
  • Multivariate Analysis
  • Obesity*
  • Odds Ratio
  • Overweight / complications
  • Patient Compliance
  • Pregnancy
  • Pregnancy Complications*
  • Weight Gain*
  • Young Adult