Gestational diabetes: insulin requirements in pregnancy

A prospective study of 57 women with gestational diabetes mellitus was undertaken to determine actual insulin requirements throughout pregnancy. Women were placed on a multiple injection, mixed insulin regimen and monitored their blood glucose level 6.5 +/- 1 times per day using a memory-based reflectance meter to obtain verified data. A significant (p less than 0.01) increase in total insulin dose was found during the initial treatment period (7 +/- 2 days) until the target glucose range was achieved. Insulin requirements continued to significantly (p less than 0.01) rise until 30 +/- 1 gestational weeks, despite a stabilization of glucose level. Thereafter, there was no significant change (3%) in insulin requirement. A correlation of r = 0.58 (p less than 0.001) for the relationship between insulin dose at the 24 and 32 weeks' gestation, and an r = 0.99 (p less than 0.0001) for the relationship between insulin dose at 32 and 39 weeks' gestation was found. We concluded that an emphasis on ambulatory blood glucose control and insulin adjustments should occur in the early treatment phase of gestational diabetes.