Objective: To evaluate the risk of hypoglycemia associated with intensive insulin therapy of type I diabetes during pregnancy.
Methods: Eighty-four women with type I diabetes were recruited before 9 weeks' gestation and received intensive insulin therapy throughout pregnancy. Patients monitored glucose concentrations with memory glucometers, and insulin dosages were adjusted weekly accordingly. A detailed history of clinical hypoglycemic events was obtained at each weekly clinic visit.
Results: Clinically significant hypoglycemia requiring assistance from another person occurred in 71% of pregnant patients, with a peak incidence between 10-15 weeks. Severe hypoglycemia during the early weeks of embryogenesis was not associated with an increase in embryopathy. Glycemic control was similar in women with or without recurrent hypoglycemia, but glucose fluctuations were significantly greater in hypoglycemic women.
Conclusion: Severe hypoglycemia is a significant maternal risk associated with intensive insulin therapy of pregnant women with type I diabetes. In women with recurrent episodes of hypoglycemia, the clear benefits of strict glycemic control must be weighed against the hazards of hypoglycemia.