The incidence of gestational diabetes mellitus (GDM) has reached epidemic proportions in the United States, affecting 200,000 pregnant women annually. Controversies exist regarding whether the glucose levels used to diagnose GDM in pregnancy should be lowered since similar fetal complications are seen in women with GDM as well as in nondiabetic women. Although GDM has been extensively studied, the effects of the earlier stage of glucose intolerance are not well understood. The objectives of this descriptive, comparative, correlational pilot study include assessment of real-time blood glucose concentrations in women (20) with idiopathic macrosomia and/or polyhydramnios but with a normal baseline glucose screening test. This group was compared to pregnant women (20) without idiopathic macrosomia and/or polyhydromnios as confirmed by normal ultrasounds (controls). All subjects had a normal screeing test and/or a 3-hour Glucose Tolerance Test earlier in the pregnancy and wore a continuous glucose monitoring system for 72 hours. No adverse maternal complications were seen. Neonatal complications included macrosomia, shoulder dystocia, and hyperbilirubinemia. There was no significant association between real-time blood glucose levels and adverse maternal or fetal/neonatal complications. There is little evidence available regarding real-time physiologic glycemic levels in pregnant women. The findings of our pilot study provide baseline data for the design of a larger study to compare blood glucose levels and complications in euglycemic women and compare to women with those impaired glucose tolerance.