Married women are more likely to have appropriate GWG than unmarried women. Intimate partner violence is associated with insufficient GWG. There is a paucity of studies examining the influence of partner/family support on GWG.
GWG is generally higher among adolescents and lower among women > 35 years of age, although the relationship of GWG among these groups to birth outcomes, postpartum weight retention, and subsequent risk for overweight/obesity remains unclear.
There is a lack of evidence on GWG among vulnerable populations, specifically, seasonal migrant workers, women in military service, and women incarcerated during pregnancy.
The IOM (1990) GWG guidelines appear to influence what women believe to be appropriate weight gain during pregnancy, though their influence on actual GWG is less clear in part because many health professionals are providing no or inappropriate advice about weight gain during pregnancy.
There is growing evidence suggesting that specific fetal and maternal genes and alleles can influence GWG, though both parental genotypes appear to affect birth weight. The effect of developmental programming and epigenetic events on GWG is strongly suspected, but direct evidence is still lacking. Leptin and adiponectin may represent markers of insulin sensitivity or other mechanisms affecting gestational weight changes.
Research Recommendation 4-1: The committee recommends that the National Institutes of Health and other relevant agencies should provide support to researchers to conduct studies in large and diverse populations of women to understand how dietary intake, physical activity, dieting practices, food insecurity and, more broadly, the social, cultural, and environmental context affect GWG.
The committee identified the following areas for further investigation to support its research recommendations. The research community should conduct studies on:
Social, cultural, and environmental contexts of GWG. Findings from these studies should help to guide the development of implementation strategies for GWG recommendations;
Health care providers’ knowledge, attitude, and behavior with respect to GWG recommendations. These studies should identify