Advances in diabetes management: have pregnancy outcomes in women with type 1 diabetes changed in the last decades?

Aims: Over the recent years multiple therapeutic and management opportunities have been made available to treat pregnant women with Type 1 diabetes (T1DM). However, analyses assessing whether these different approaches may have any specific advantage/disadvantage in metabolic control and neonatal outcomes is still limited. To compare metabolic control and neonatal outcomes in pregnant women with T1DM among different basal insulins (NPH vs. analogue), insulin administration ways [Multiple Daily Injections (MDI) vs. Continuous Subcutaneous Insulin Infusion (CSII)] and glucose monitoring systems [Self-Monitoring of Blood Glucose (SMBG) vs. real-time/intermittently scanned Continuous Glucose Monitoring (rtCGM/isCGM)].Methods: A retrospective analysis on metabolic data and neonatal outcomes of 136 T1DM pregnant women (76% on MDI, based on NPH(51%) or analogue(49%); 24% on CSII; 24% using rtCGM/isCGM), managed between 2008 and 2020, was performed, comparing different therapeutic approaches.Results: Metabolic data and neonatal outcomes were comparable among women treated with different basal insulins. Women on CSII planned their pregnancy more frequently (82vs.60%; p=0.043) and had better pregestational HbA1c (52 +/- 5 vs. 60 +/- 13mmol/mol; p=0.044) and first trimester HbA1c (48 +/- 4 vs. 51 +/- 8 mmol/mol; p=0.047), respectively. Pregestational and first trimester HbA1c were also lower in women using rtCGM/isCGM (53 +/- 8 vs. 58 +/- 13mmol/mol; p=0.027 and 46 +/- 5 vs. 51 +/- 7mmol/mol; p=0.034, respectively). In the whole cohort, LGA risk was directly correlated to HbA1c at third trimester (correlation coefficient 0.335, p=0.001) and inversely correlated to the achievement of HbA1c target (<= 6% [<42 mmol/mol]) at third trimester (correlation coefficient - 0.367, p <0.001).Conclusion: Treatment with insulin analogs didn't significantly change metabolic control and neonatal outcomes in T1DM women, while CSII and rtCGM/isCGM can optimize preconception and first trimester pregnancy glycemic control. Irrespective of the therapeutic management, third trimester HbA1c remains the strongest risk factor for LGA.