The relationship between carbohydrate intake and glucose tolerance in pregnant women.
OBJECTIVE
We verified whether a misdiagnosis of gestational diabetes mellitus can result in pregnant women when glucose tolerance has deteriorated after a low-carbohydrate meal, and tried to elucidate the mechanism behind the different outcome of the test.


METHODS
Twenty-seven pregnant women were given directions for their evening meal the day before each of two 75-g oral glucose tolerance tests (OGTT). The evening meal was either a low-carbohydrate meal (carbohydrate, 6.7%; Low), or a high-carbohydrate meal (carbohydrate, 85.7%; High).


RESULTS
The OGTT showed that the glucose tolerance was significantly impaired after Low than after High, with a significant increase of fasting plasma non-esterified fatty acids (NEFA) level. Moreover, the insulinogenic index (I-I) after High significantly decreased than that after Low.


CONCLUSIONS
The present data suggests that there is a risk of misdiagnosis of impaired glucose tolerance with only one intake of this extremely low-carbohydrate meal on the evening before testing. The decrease of insulin secretion and the activation of glucose-fatty acid cycle may be considered as the mechanism.
Takizawa
Motoi
M
Department of Obstetrics and Gynecology, Yamanashi Medical University, Tamaho, Yamanashi, Japan.
Kaneko
Takashi
T
Kohno
Keiko
K
Fukada
Yukihito
Y
Hoshi
Kazuhiko
K
D000328:Adult; D015331:Cohort Studies; D016640:Diabetes, Gestational / Q000175:diagnosis*; D003937:Diagnosis, Differential; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D005865:Gestational Age; D018149:Glucose Intolerance / Q000175:diagnosis*; D005951:Glucose Tolerance Test; D006801:Humans; D011247:Pregnancy; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity
D004040:Dietary Carbohydrates