Accurate knowledge of changes in plasma glucose levels during pregnancy and parturition in normoglycemic women is important for safe management of hyperglycemic disorders in pregnancy. However, there are few reports showing long-term changes in glucose levels over the entire pregnancy period. Flash glucose monitoring (FGM) is a new sensor technology that enables us to ascertain these glucose levels. This is the first study in Japan to monitor glucose levels during this period in normoglycemic, pregnant women by using FGM, which was performed once in non-pregnant women and up to 5 times (first trimester, second trimester, third trimester, parturition, and 3-month postpartum) in pregnant women. Twenty-one non-pregnant women and 9 pregnant women participated in the study. In non-pregnant women, the average age and BMI were 34.4±9.1 years and 20.4±1.5 kg/m2, respectively; the average glucose level was 101.9±20.8 mg/dL, with no difference in age groups. In pregnant women, the average age and BMI were 33.0±2.7 years and 19.0±1.4 kg/m2, respectively. The average glucose levels were 99.8±5.0 mg/dL at first trimester, 85.1±13.0 mg/dL at second trimester, 92.0±7.6 mg/dL at third trimester, 107.3±8.1 mg/dL during parturition, and 95.7±10.0 mg/dL at 3-month postpartum. Compared to glucose levels of non-pregnant women, those of pregnant women were significantly lower at second and third trimester, and returned to the same level at 3-month postpartum. The glucose level during parturition was significantly highest; the proportion of time to achieve optimal target glucose level of 80-110 mg/dL was 62.3±19.9% and the highest value was 244 mg/dL. Maternal and neonatal clinical courses were uneventful in all pregnant cases. It is thus necessary to evaluate to what extent peak value and duration of hyperglycemia affects birth outcome.


A. Nishimura: None. M. Furuta: None. Y. Chigusa: None. M. Maeno: None. M. Fukami: None. S. Harashima: Advisory Panel; Self; Novo Nordisk Inc.. Speaker's Bureau; Self; Novo Nordisk Inc.. Research Support; Self; AstraZeneca. Speaker's Bureau; Self; Sanofi K.K.. Research Support; Self; Sanofi K.K.. Speaker's Bureau; Self; Tanabe Mitsubishi KK. Advisory Panel; Self; Tanabe Mitsubishi KK. Speaker's Bureau; Self; Novartis Pharma K.K., Eli Lilly and Company, Ono Pharmaceutical Co., Ltd..

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