Recommendation and intake of dietary supplements periconceptional and during pregnancy: results of a nationwide survey of gynaecologists

BACKGROUND: Micronutrient supplementation during pregnancy is a controversial issue. For some micronutrients, for example folic acid or iodine, the evidence regarding supplementation is clear, whereas for others, such as zinc or vitamin E, it is not. Studies show that a large number of pregnant women have deficient levels of folic acid and iodine. However, especially with folic acid, starting supplementation during the preconception period is crucial. It is, therefore, important that gynaecologists explain this to their pregnant or preconceptional patients. Our goal was to find out how gynaecologists make their recommendations on this topic, how they assess the compliance of their patients and which micronutrients they consider to be important before/during pregnancy and during breastfeeding. METHOD AND RESULTS: We sent about 12,000 questionnaires to all registered resident gynaecologists in Germany, with a response rate of 12.2%. Regarding which micronutrients gynaecologists consider to be particularly important during pregnancy, there was a broad agreement for both folic acid and iodine (> 88% answered yes). According to the questionnaire, doctors rate other micronutrients, such as vitamin D and omega-3 fatty acids, as less essential. The controversial evidence level for many micronutrients certainly plays a role here. Overall, the intake rate, especially for preconceptional women, is classified as rather low (< 60%). The most widely valued reason is the high price of dietary supplements. It was also noticeable that doctors consider certain micronutrients to be particularly important but then do not include them in the products they recommend. CONCLUSION: Overall, there seems to be uncertainty about micronutrients in pregnancy and their supplementation. The study situation is often ambiguous and there are no official guidelines, leading to ambiguous recommendations from doctors and therefore low intake rates for pregnant or preconceptional women. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00404-023-07167-6.