According to a recent study, depression in early pregnancy doubles the risk for gestational diabetes, and gestational diabetes increases risk for postpartum depression. The finding suggests that doctors should pay particular attention to patients with either condition. The study does not show a cause and effect relationship between the conditions. NIH researchers note, however, that previous studies have linked depression and impaired glucose metabolism, which leads to higher blood sugar levels. Higher blood sugar levels often lead to inflammation and hormonal changes linked to symptoms of depression.