Association between preconception dietary fiber intake and hypertensive disorders of pregnancy: The Japan Environment and Children’s Study

•Hypertensive disorders of pregnancy (HDP) are significant maternal complications.•Preconception dietary fiber intake was associated with the risk of HDP.•Increased dietary fiber intake may offer protection against the onset of HDP.•Preconception care is crucial for preventing the onset of HDP. Hypertensive disorders of pregnancy (HDP) are a significant cause of morbidity and mortality. This study aimed to investigate whether preconception dietary fiber intake is associated with new-onset HDP. We identified 84,873 (primipara, 33,712; multipara, 51,161) normotensive participants from the Japan Environmental Children’s Study database who delivered between 2011 and 2014. The participants were subsequently categorized into five groups based on their preconception dietary fiber intake quintiles (Q1–Q5). The main obstetric outcome was HDP, and the secondary obstetric outcomes included early-onset (Eo,