The Relationship Between Pregnancy Intentions and Diet or Physical Activity Behaviors in the Preconception and Antenatal Periods: A Systematic Review and Meta-Analysis

Introduction Healthy preconception and antenatal diet and physical activity behaviors may optimize maternal and offspring outcomes. These behaviors are thought to be linked to pregnancy intentions. The aim of this study was to conduct a systematic review and meta-analysis to determine the association between women's pregnancy intentions and diet or physical activity behaviors in the preconception and antenatal periods. Methods MEDLINE Complete, PsycINFO, CINAHL Complete, Global Health, Embase, and INFORMIT: Health Subset were searched in September 2018 for studies that evaluated relationships between pregnancy intentions and dietary and physical activity behaviors. Risk of bias was assessed, and random effects meta-analyses were conducted for dietary (food groups; energy and macronutrients; diet quality; and caffeine, iodine, and folate intake) and physical activity outcomes. Results Of 2623 screened records, 19 eligible studies were identified. The overall risk of bias was moderate to high. Twelve studies measured diet and physical activity behaviors during preconception, 5 during pregnancy, and 2 across both periods. Eleven studies measured pregnancy intention retrospectively, and 8 prospectively measured pregnancy intention. The number of studies available for meta-analyses of individual dietary and physical activity outcomes ranged from 2 to 5. Pregnancy intentions were not associated with preconception fruit, vegetable, or caffeine intake or physical activity. Antenatally, women with intended pregnancies were more likely to report healthier diets, lower caffeine intake, and higher physical activity. Insufficient studies were available to conduct subgroup comparisons for prospective or retrospective assessment. Discussion Pregnancy intentions were not associated with preconception diet or physical activity behaviors. In contrast, antenatally, women with intended pregnancies demonstrated better diet and physical activity behaviors. Given the small number of studies available for meta-analyses, further research is needed to consolidate our findings. Meanwhile, health professionals can assess women's pregnancy intentions during preconception and pregnancy and encourage a healthy lifestyle.