Is there a difference in pregnancy and glycemic outcome in patients with type 1 diabetes on insulin pump with constant or intermittent glucose monitoring? A pilot study.

BACKGROUND: The aim of the study is to describe glycemic and insulin outcomes by trimester and maternal and fetal outcome in patients with type 1 diabetes using an insulin pump with constant or intermittent continuous glucose monitoring (CGM).

METHODS: Twenty-five women with type 1 diabetes with newly diagnosed pregnancy were treated with insulin pump therapy (Medtronic 722, Medtronic Minimed, Northridge, CA) for at least 1 year. Insulin pump and CGM (Medtronic Paradigm Real-Time) were implemented at least 3 months before conception. Patients were randomized in two groups: constant CGM group, 12 patients on insulin pump with glucose sensor, 24 h/day; and intermittent CGM group, 13 patients on insulin pump with intermittent glucose sensor, 14 days/month. The following parameters were analyzed: glycosylated hemoglobin (HbA1c), mean blood glucose, insulin requirement (in IU/kg/day), weight gain, severe hypoglycemic events, diabetic ketoacidosis, macrosomia, cesarean section, and neonatal hypoglycemia.

RESULTS: Both groups achieved good glucose control during their pregnancies (P<0.05): 6.78±1.3% and 6.92±0.9% at the beginning of the study compared with 6.14±0.9% (constant CGM group) and 6.23±0.6% (intermittent CGM group) at the end of the study (last HbA1c before delivery). There was no significant decrease of HbA1c between the two groups. The constant CGM group had a significantly lower A1c in the first trimester compared with the intermittent CGM group. Maternal and fetal outcome did not show a significant difference between the two groups.

CONCLUSIONS: Insulin pump therapy together with constant or intermittent CGM can improve diabetes control and pregnancy outcome in type 1 diabetes. The quality of the glucose profile at conception was the important factor for pregnancy outcome.