Insulin antibodies do not preclude optimization of metabolic control in women with IDDM during pregnancy

OBJECTIVE - To evaluate whether the presence of insulin antibodies (IAs) may preclude the optimization of metabolic control during pregnancy and affect outcome in women with IDDM. RESEARCH DESIGN AND METHODS - IAs were measured by radiobinding assay in 44 women with IDDM referred to the Diabetes and Pregnancy Outpatients' Clinic during 46 pregnancies. Age, duration of IDDM, metabolic control (HbA(1c), mean pre- and postprandial capillary blood glucose, frequency of hypo- or hyperglycemia), insulin requirement at 1st and 3rd trimester of pregnancy, BMI, and weight gain were recorded. Neonatal variables such as gestational age, weight, length, and the presence at birth of either hypoglycemia, hypocalcemia, or jaundice requiring phototherapy were also considered. RESULTS - IAs correlated positively with insulin requirement (P < 0.05) and negatively with HbA,, at term (P < 0.01). Patients with IA levels greater than or equal to 40% insulin binding (8 of 46) had a higher insulin requirement and lower preprandial capillary blood glucose at the beginning of pregnancy but not at term (P < 0.005), whereas they had lower HbA(1c) at term than did patients with low IA levels (P < 0.01). IA levels decreased slightly at term (P = 0.007). IA levels greater than or equal to 40% were not associated with a higher rate of hypo- or hyperglycemic episodes or with diabetic complications or thyreopathy. No correlation was found between IA levels and any of the neonatal variables considered. CONCLUSIONS - The presence of IAs does not preclude optimization of metabolic control during pregnancy and is compatible with a favorable outcome.