This cross-sectional study included a cohort of 1745 pregnant Japanese women. Dietary intake during the preceding month was assessed using a self-administered diet history questionnaire. Scores of 16 or higher on the Center for Epidemiologic Studies Depression Scale denoted depressive symptoms. Various adjustments were made for different confounding factors (age, pregnancy, number of children, history of depression, dietary intake of fish, vitamin D and saturated fatty acids etc.).
Higher intake levels of yogurt and calcium were independently related to a lower prevalence of depressive symptoms during pregnancy, with adjusted odds ratios between extreme quartiles of 0.69 and 0.59 respectively. No relationships were observed between the intake of all dairy products, milk, or cheese and depressive symptoms during pregnancy.