Treatment of severe insulin resistance in pregnancy with 500 units per milliliter of concentrated insulin.

Objective: To evaluate glycemic control and pregnancy outcomes among pregnant women with severe insulin resistance treated with 500 units/mL concentrated insulin.

Methods: Retrospective analysis of gravid women with severe insulin resistance (need for greater than 100 units of insulin per injection or greater than 200 units/d) treated with either 500 units/mL concentrated insulin or conventional insulin therapy. We performed a two-part analysis: 1) between gravid women treated with and without 500 units/mL concentrated insulin; and 2) among gravid women treated with 500 units/mL concentrated insulin, comparing glycemic control before and after its initiation.

Results: Seventy-three pregnant women with severe insulin resistance were treated with 500 units/mL concentrated insulin and 78 with conventional insulin regimens. Patients treated with 500 units/mL concentrated insulin were older and more likely to have type 2 diabetes mellitus. Average body mass index was comparable between both groups (38.6 compared with 40.4, P=.11) as were obstetric and perinatal outcomes and glycemic control during the last week of gestation. Within the 500 units/mL concentrated insulin cohort, after initiation of this medication, fasting and postprandial blood glucose concentrations improved. However, the rates of blood glucose values less than 60 mg/dL and less than 50 mg/dL were higher in the 500 units/mL concentrated insulin group after initiation than before, 4.8% compared with 2.0% (P<.01) and 2.0% compared with 0.7% (P<.01), respectively.

Conclusion: The use of 500 units/mL concentrated insulin in severely obese insulin-resistant pregnant women confers similar glycemic control compared with traditional insulin regimens but may increase the risk of hypoglycemia.

Level Of Evidence: II.