The preconception nutritional status of women undergoing fertility treatment: Use of a one-year post-delivery assessment

Background&Aims - A poor maternal nutritional status in the preconception period is associated with adverse pregnancy outcomes. A valid standardized assessment period after pregnancy reflecting the preconception nutritional status is missing. Therefore, this study aimed to validate the assessment period at around 1 year after delivery in women undergoing fertility treatment. Methods - In a prospective study including 30 women with a fertility problem, we compared nutrient intakes from a food frequency questionnaire and biomarkers related to the homocysteine pathway in blood, at two assessment periods, i.e., preconceptionally and 1 year after delivery. We used a linear mixed model and adjusted for possible confounders, such as body mass index and folic acid supplement use. Results - The energy-adjusted nutrient intakes were not significantly different between the two assessment periods, except for higher retinol, alcohol and vitamin B2 and lower carbohydrate intakes at around 1 year after delivery. The intraclass correlation coefficients of the nutrients ranged from 0.3 to 0.7. After adjustment, none of the biomarkers was significantly different between the two assessment periods. The intraclass correlation coefficients of the biomarkers were all =0.5. Conclusions - An assessment at around 1 year after delivery seems to adequately reflect the preconception nutritional status of women with a fertility problem, however larger confirmatory studies are required