Maternal and Child Health Journal

, Volume 12, Issue 5, pp 557–567

Pre-pregnancy Body Mass Index, Gestational Weight Gain, and Other Maternal Characteristics in Relation to Infant Birth Weight

Authors

    • Department of Health ServicesUniversity of Washington School of Public Health and Community Medicine
    • Swedish Medical CenterCenter for Perinatal Studies
  • Michelle A. Williams
    • Swedish Medical CenterCenter for Perinatal Studies
    • Department of EpidemiologyUniversity of Washington School of Public Health and Community Medicine
  • Anne E. Sales
    • Department of Health ServicesUniversity of Washington School of Public Health and Community Medicine
    • Veterans’ Administration Puget Sound Health Care Systems
    • Faculty of NursingUniversity of Alberta
  • Diane P. Martin
    • Department of Health ServicesUniversity of Washington School of Public Health and Community Medicine
  • Marcia Killien
    • Department of Family and Child Health NursingUniversity of Washington School of Nursing
Article

DOI: 10.1007/s10995-007-0276-2

Cite this article as:
Frederick, I.O., Williams, M.A., Sales, A.E. et al. Matern Child Health J (2008) 12: 557. doi:10.1007/s10995-007-0276-2

Abstract

Objectives Infant birth weight is influenced by modifiable maternal pre-pregnancy behaviors and characteristics. We evaluated the relationship among pre-pregnancy body mass index (BMI), gestational weight gain, and infant birth weight, in a prospective cohort study. Methods Women were enrolled at ≤20 weeks gestation, completed in-person interviews and had their medical records reviewed after delivery. Infant birth weight was first analyzed as a continuous variable, and then grouped into Low birth weight (LBW) (<2,500 g), normal birth weight (2,500–3,999 g), and macrosomia (≥4,000 g) in categorical analysis. Pre-pregnancy BMI and gestational weight gain were categorized based on Institute of Medicine BMI groups and gestational weight gain guidelines. Associations among infant birth weight and pre-pregnancy BMI, gestational weight gain, and other factors were evaluated using multivariate regression. Risk ratios were estimated using generalized linear modeling procedures. Results Pre-pregnancy BMI was independently and positively associated with infant birth weight (β = 44.7, P = 0.001) after adjusting for confounders, in a quadratic model. Gestational weight gain was positively associated with infant birth weight (β = 19.5, P < 0.001). Lower infant birth weight was associated with preterm birth (β = −965.4, P < 0.001), nulliparity (β = −48.6, P = 0.015), and female babies (β = −168.7, P < 0.001). Less than median gestational weight gain was associated with twice the risk of LBW (RR = 2.04, 95% CI 1.34–3.11). Risk of macrosomia increased with increasing pre-pregnancy BMI and gestational weight gain (P for linear trend <0.001). Conclusions These findings support the need to balance pre-pregnancy weight and gestational weight gain against the risk of LBW and macrosomia among lean and obese women, respectively.

Keywords

Body mass indexWeight gainBirth weightCohort study

Copyright information

© Springer Science+Business Media, LLC 2007