Changes in Diet and Exercise in Pregnant Women after Diagnosis with Gestational Diabetes: Findings from a Longitudinal Prospective Cohort Study.

BACKGROUND:Lifestyle changes are recommended for women diagnosed with gestational diabetes mellitus (GDM), yet there are few data available documenting whether women change their diet and exercise after GDM diagnosis. OBJECTIVE:The aim of this study was to assess whether, and to what extent, pregnant women receiving usual prenatal care change their diet and exercise after a GDM diagnosis. DESIGN:This study was a post-hoc secondary analysis using data from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies-Singletons (2009-2013), a prospective pregnancy cohort study. PARTICIPANTS/SETTING:Pregnant US women without major chronic medical conditions were enrolled from 12 participating hospital centers at 8 to 13 weeks' gestation. Diet analyses were based on 5,194 dietary recalls from 1,371 women. Exercise analyses were based on 6,440 physical activity assessments from 1,875 women. GDM was ascertained from medical records according to Carpenter and Coustan criteria. Women completed 24-hour dietary recalls and exercise assessments at weeks 16 to 22, 24 to 29, 30 to 33, 34 to 37, and 38 to 41 (exercise only). MAIN OUTCOME MEASURES:The main outcome was the diet and exercise change from before to after GDM diagnosis or screening. STATISTICAL ANALYSES:Diet and exercise changes with 95% CIs from before to after GDM diagnosis or screening for women with and without GDM were estimated using weighted multivariable linear mixed models. RESULTS:Women with GDM (n = 72) significantly reduced their total energy intake (-184 kcal/d; 95% CI -358 to -10 kcal/d) and carbohydrate intake (-47.6 g/d; 95% CI -71.4 to -23.7 g/d) from before to after GDM diagnosis; these changes were unique to women with GDM and not observed among women without GDM (n = 1,299). Women with GDM decreased intakes of juice (-0.4 cups/d; 95% CI -0.7 to -0.2 cups/d) and added sugar (-3.2 teaspoons/d; 95% CI -5.5 to -0.5 teaspoons/d) and increased cheese (0.3 cups/d; 95% CI 0.1 to 0.6 cups/d) and artificially sweetened beverages (0.2 cups/d; 95% CI 0.0 to 0.3 cups/d). Women with GDM (n = 84) did not change their exercise duration after diagnosis; women without GDM (n = 1,791) significantly decreased moderate (-19.5 min/wk; 95% CI -24.7 to -14.3 min/wk) and vigorous exercise (-8.8 min/wk; 05% CI -10.6 to -6.9 min/wk) after GDM screening. CONCLUSIONS:Women with GDM made modest dietary improvements and maintained their prediagnosis exercise routine, yet opportunities remain to further improve dietary intake and exercise after a diagnosis of GDM.