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In May 2009, the Institute of Medicine (IOM) introduced revised gestational weight gain guidelines that were based on balancing the benefits and risks of weight gain for both the mother and child's health. This article provides an overview of these new recommendations, explaining the key changes made from the previous 1990 IOM recommendations. The important role of health care providers of pregnant women in the implementation of the new recommendations is detailed, and specific guidance for troubleshooting issues that may be encountered when helping women achieve appropriate gestational weight gains is provided.

Postpartum weight retention plays an important role in the pathway leading to obesity among women of childbearing age. The objective of this study was to examine predictors of moderate (1-10 pounds) and high (>10 pounds) postpartum weight retention using data from a prospective pregnancy cohort that followed women into the postpartum period; n = 688 and 550 women at 3 and 12 months, respectively. Analysis included descriptive statistics and predictive modeling using log-binomial techniques. The average weight retained at 3 and 12 months postpartum in this population was 9.4 lb (s.d. = 11.4) and 5.7 lb (s.d. = 13.2), respectively. At 3 months postpartum, prepregnancy weight, gestational weight gain, and hours slept during the night were associated with moderate or high weight retention, whereas having an infant hospitalized after going home and scoring in the upper 75th percentile of the Eating Attitudes Test (EAT) were associated only with high weight retention. At 12 months postpartum, prepregnancy weight, gestational weight gain, and maternal education were associated with moderate weight retention; and gestational weight gain, maternal age, race, employment status, and having an infant hospitalized at birth were associated with high weight retention. The results of this study illustrate the importance of prepregnancy weight and gestational weight gain in predicting postpartum weight retention. Furthermore, given the lack of successful intervention studies that exist to date to help women lose weight in the postpartum period, the results of this study may help to inform future interventions that focus on such aspects as hours of sleep, dealing with stress associated with a hospitalized infant, and nonclinical eating disorder symptomatology.

This systematic review focuses on outcomes of gestational weight gain, specifically birthweight, fetal growth, and postpartum weight retention, for singleton pregnancies with respect to the 1990 Institute of Medicine weight gain recommendations. A total of 35 studies met the inclusion criteria and were reviewed. There was strong evidence to support associations between excessive gestational weight gain and increased birthweight and fetal growth (large for gestational age) as well as inadequate gestational weight gain and decreased birthweight and fetal growth (small for gestational age). There was moderate evidence to support the association between excessive gestational weight gain and postpartum weight retention. Clear clinical recommendations based on this review are challenging because of several limitations in the literature. Improvements in future research include the use of consistent definitions of gestational weight gain and outcomes of interest, assessment of confounders, and better collection of weight and weight gain data.

BACKGROUND: Most pregnant women gain more weight than the ranges recommended. Excessive weight gain is linked to pregnancy complications and to long-term maternal and child health outcomes. OBJECTIVE: The objective was to examine the impact of dietary glycemic load and energy density on total gestational weight gain and the weight gain ratio (observed weight gain/expected weight gain). DESIGN: Data are from 1231 women with singleton pregnancies who participated in the Pregnancy, Infection, and Nutrition Cohort Study. Dietary information was collected at 26-29 wk of gestation with the use of a semiquantified food-frequency questionnaire. Linear regression models were used to estimate the associations between quartiles of glycemic load and energy density with total gestational weight gain and weight gain ratio. RESULTS: Dietary patterns of pregnant women significantly differed across many sociodemographic and behavioral characteristics, with the greatest contrasts seen for glycemic load. After adjustment for covariates, compared with women in the first quartile consuming a mean dietary energy density of 0.71 kcal/g (reference), women in the third quartile consuming a mean energy density of 0.98 kcal/g gained an excess of 1.13 kg (95% CI: 0.24, 2.01), and women in the fourth quartile consuming a mean energy density of 1.21 kcal/g gained an excess of 1.08 kg (95% CI: 0.20, 1.97) and had an increase of 0.13 (95% CI: 0.006, 0.24) units in the weight gain ratio. All other comparisons of energy intakes were not statistically significant. Glycemic load was not associated with total gestational weight gain or weight gain ratio. CONCLUSION: Dietary energy density is a modifiable factor that may assist pregnant women in managing gestational weight gains.

OBJECTIVES: The RTI International-University of North Carolina at Chapel Hill Evidence-based Practice Center (RTI-UNC EPC) systematically reviewed evidence on outcomes of gestational weight gain and their confounders and effect modifiers, outcomes of weight gain within or outside the 1990 Institute of Medicine (IOM) guidelines, risks and benefits of weight gain recommendations, and anthropometric measures of weight gain. DATA SOURCES: We searched MEDLINE Cochrane Collaboration resources, Cumulative Index to Nursing & Allied Health Literature, and Embase. REVIEW METHODS: We included studies published in English from 1990 through October 2007. We excluded studies with low sample size (based on study design: case series <100 subjects and cohorts <40 subjects). RESULTS: Overall, strong evidence supported an association between gestational weight gains and the following outcomes: preterm birth, total birthweight, low birthweight (<2,500 g), macrosomia, large-for-gestational-age (LGA) infants, and small-for-gestational-age (SGA) infants; moderate evidence supported an association for cesarean delivery and intermediate-term weight retention (3 months to 3 years postpartum). The studies reviewed provided strong evidence for the independent association of pregravid weight status and outcomes, moderate evidence for age and parity, and weak evidence for race. Regarding outcomes of weight gain within or outside 1990 IOM guidelines, moderate to strong evidence suggests an association between weight gain below IOM recommendations and preterm birth, low birthweight, SGA birthweights, and failure to initiate breastfeeding, and strong evidence for the association between weight gain above IOM recommendations and high birthweight, macrosomia, and LGA birthweights. Moderate evidence supports an association between weight gain above IOM guidelines and cesarean delivery and postpartum weight retention in the short, intermediate, and long term. Included research is inadequate for objective assessments of the range of harms and benefits of providing all women, irrespective of age, race or ethnicity, or pregravid body mass index (BMI), with the same recommendation for weight gain in pregnancy. CONCLUSIONS: Gestational weight gain is associated with some infant and maternal outcomes. One weight gain recommendation for all women is not supported by the evidence identified in this review. To understand fully the impact of gestational weight gain on short- and long-term outcomes for women and their offspring will require that researchers use consistent definitions of weight gain during pregnancy, better address confounders in their analyses, improve study designs and statistical models, and conduct studies with longer followup.