The relationship between pregnancy intentions and diet or physical activity behaviours in the preconception and antenatal periods: A systematic review and meta-analysis

Isaac Nkrumah, Madelon North, Emily J Kothe, Tze Lin Chai, Stephanie Pirotta, Siew Lim, Briony Hill

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Introduction: Healthy preconception and antenatal diet and physical activity behaviours are crucial to prevent adverse maternal and offspring outcomes. These behaviours 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 behaviours 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 behaviours. 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. Overall risk of bias was moderate to high. Twelve studies measured diet/physical activity behaviours 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/retrospective assessment. Discussion: Pregnancy intentions were not associated with preconception diet or physical activity behaviours. In contrast, antenatally, women with intended pregnancies demonstrated better diet and physical activity behaviours. 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. PROSPERO registration number CRD42018107854.
Original languageEnglish
Number of pages47
JournalJournal of Midwifery & Women's Health
Publication statusAccepted/In press - 10 Mar 2020


  • Pregnancy intentions
  • ‘pregnancy, unplanned’
  • preconception
  • pregnancy
  • diet
  • physical activity

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