DIABETIC TESTING
1-h 50-g oral glucose tolerance test (OGTT): screening test administered to
all pregnant women between 24–28 weeks’ gestation (no fasting state is
needed). A 50-g glucose load is given, and serum glucose is measured 1 h
later. A normal value is <140 mg/dL. An abnormal value is ≥140 mg/dL
(15% of pregnant women). Management is a 3-h 100-g OGTT.
3-h 100-g OGTT: definitive test for glucose intolerance in pregnancy (15%
of women with an abnormal screening test will be found to have gestational
diabetes mellitus). After an overnight fast, a fasting blood sugar (FBS) is
drawn. An FBS value >125 mg/dL indicates overt diabetes mellitus, and no
further testing is performed. An FBS value <126 mg/dL requires
administration of a 100-g glucose load, followed by glucose levels at 1, 2, and
3 h.
Normal values are FBS <95 mg/dL, 1 h <180 mg/dL, 2 h <155 mg/dL,
and 3 h <140 mg/dL.
Gestational diabetes is diagnosed if ≥2 values are abnormal.
Impaired glucose intolerance is diagnosed if only 1 value is abnormal.http://ebookobgyne.net