Nutritional intake and determinants of nutritional quality changes from pregnancy to postpartum-a longitudinal study

Nutrient requirements vary across the reproductive cycle, but research on changes in nutritional intake and quality from pregnancy to beyond the lactation period is limited. Thus, we aimed to study nutritional intake and quality changes, among Swedish pregnant participants from late pregnancy to 18 months postpartum and to study the determinants of nutritional quality changes. Participants (n = 72) were studied longitudinally from the third trimester of pregnancy and postpartum (2 weeks 4, 12, and 18 months postpartum). At each visit, participant characteristics and 4-day food diaries were collected. Nutritional quality was assessed by energy adjusted Nutrient Rich Food Index 11.3. Linear mixed models were used to analyze the determinants of change in nutritional quality. Intakes of carbohydrate energy percentage (E%), fiber, vitamin A, vitamin C, and potassium were higher in the third trimester compared to postpartum, whereas intakes of E% protein and monounsaturated fat were lower. Adherence to recommended intakes was low at all study visits for saturated fat (4%-11%), fiber (15%-39%), vitamin D (8%-14%), folate (0%-2%), and iron (6%-21%). Overall, nutritional quality did not differ significantly from third trimester to postpartum. Shorter duration (<4 months) of lactation was negatively related to nutritional quality changes, whereas higher age was positively related to changes. In conclusion, nutritional intake from pregnancy to postpartum changed, whereas quality remained relatively stable, with age and lactation duration as determinants. Identification of people at risk of adverse dietary changes from pregnancy to the postpartum period should be further addressed in future larger and more diverse study populations.