Adherence to recommendations for nutrient supplementation related to pregnancy in Germany.

Supplementation of certain micronutrients is recommended to ensure their adequate supply during pregnancy and lactation. In Germany, this applies particularly to folic acid and iodine. There is no nationwide data on adherence to the supplementation guidelines. The aim of this cross-sectional study was to determine the prevalence and predictors of the recommended supplementation of both folic acid and iodine in mothers of a nationwide birth cohort. Data on supplementation, before, during, and shortly after pregnancy, were collected retrospectively 14 days postpartum in a sample of 962 mother-infant pairs participating in the second nationwide study on breastfeeding and infant nutrition in Germany, called "SuSe II" (2017-2019). Folic acid and iodine supplementation were classified as recommended according to the German guidelines if supplementation was provided for both essential periods: for folic acid before and during pregnancy and for iodine during pregnancy and lactation. Univariable tests and multivariable logistic regression analysis were performed. The vast majority of mothers did not adhere to the recommendations, with only 36.2% supplementing folic acid and 31.9% supplementing iodine during the recommended periods, and only 15.2% adhering to the recommendations for both nutrients. Main predictors of adherence to recommendations of both nutrients were lifestyle attributes and nutrition-related intentions like previous breastfeeding experience and breastfeeding intentions, but not common sociodemographic characteristics. The data suggest widespread dissemination of the time-specific recommendations covering the entire period from preconception to lactation that could help to sensitize women and healthcare providers.