Glycemic control and maternal and fetal outcomes in pregnant women with type 1 diabetes according to the type of basal insulin.

OBJECTIVE: To examine the potential role of the type of basal insulin on glycemic control and maternal and foetal outcomes in pregnant women with type 1 diabetes (T1DM).

STUDY DESIGN: Retrospective cohort study of pregnancies attended at 18 Spanish tertiary hospitals.

INCLUSION CRITERIA: T1DM, singleton pregnancies, delivery between 2002-2010, and use of the same basal and prandial insulin from before pregnancy until delivery.

RESULTS: A total of 1534 pregnancies were included. The basal insulin most commonly used was Neutral Protamine Hagedorn (NPH) (51.7%), followed by glargine (23.2%) and continuous subcutaneous insulin infusion (CSII) (21.1%). CSII users had longer diabetes duration. Multiple logistic regression analysis showed that CSII was independently associated with lower doses of insulin, higher glycated haemoglobin (HbA1c ) in all trimesters, and higher rates of miscarriage, preterm birth and neonatal hypoglycemia. Glargine was related to a higher risk of preterm birth and a small-for-gestational age infant (SGA). The odds ratios (OR) of the associations between insulin type and clinical outcomes (from 0.642 to 4.894) have a relevant magnitude.

CONCLUSIONS: In this observational study of pregnant women with T1DM, the type of basal insulin was independently associated with metabolic variables and foetal outcomes.