A reappraisal of "tight control" in diabetic pregnancies

The records of 130 diabetic patients, classified by the White system (76 Class A; 54 insulin dependent), were analyzed to see whether control of diabetes, reflected as mean glucose concentration or HbA1C, is predictive of fetal weight. Fetal overgrowth was found to be common despite adequate (good or fair) control of diabetes by conventional criteria. Neither class of diabetes nor adequacy of control was correlated with fetal overgrowth, and HbA1C data followed the same trend. The failure to find an association between birth weight and HbA1C could stem from the control not being tight enough or the birth weight being more appreciably affected by other factors overshadowing the effect of control. HbA1C reflects long-term control and may serve as a useful summarizing statement.