OBJECTIVES:The current study sought to identify macroscopic placental changes associated with clinical conditions in women with or without diabetes and their newborns.METHODS:The study population consisted of 62 pregnant women clinically diagnosed with diabetes and 62 healthy women (control group).RESULTS:Among the subjects with diabetes, 43 women (69.3%) were diagnosed with gestational diabetes mellitus, 15 had diabetes mellitus I (24.2%), and four had diabetes mellitus II (6.5%). The mean age of the women studied was 28.5±5.71 years, and the mean gestational age of the diabetic women was 38.51 weeks. Of the 62 placentas from diabetic pregnancies, 49 (79%) maternal surfaces and 59 (95.2%) fetal surfaces showed abnormalities, including calcium and fibrin deposits, placental infarction, hematoma, and fibrosis. A statistical association was found between newborn gender and fetal and maternal placental changes (p = 0.002). The mean weight of the newborns studied was 3,287±563 g for women with diabetes mellitus, 3,205±544 g for those with gestational diabetes mellitus, 3,563±696 g for those with diabetes mellitus II, and 3,095±451 g for those with diabetes mellitus I.CONCLUSIONS:Infarction, hematoma, calcification, and fibrin were found on the maternal and fetal placental surfaces in women with diabetes. Women with gestational diabetes and post-term infants had more calcium deposits on the maternal placental surface as compared to those with type I and type II diabetes.