258-OR: The Effect of Early Initiation of Treatment on Glycemia and Pregnancy Outcomes in Women with Early Gestational Diabetes Mellitus

Aim: To compare maternal glycemia and pregnancy outcomes with treatment initiation before 20 weeks’ versus after 24 weeks' gestation among women with early gestational diabetes mellitus (EGDM). Methods: This prospective study included participants enrolled in the Treatment of Booking Gestational Diabetes Mellitus randomized controlled trial. Women diagnosed with GDM were provided with an Accu-Chek Guide glucose meter and instructed to monitor capillary blood glucose (BG) 4 times/day (fasting and 2-h post-prandial). Optimal glycemia was defined as 95% of BG measurements between 3.5 and 7.8 mmol/l. Pregnancy complications comprised a composite of preterm birth, macrosomia, birth trauma, respiratory distress, phototherapy, stillbirth/neonatal death, and/or shoulder dystocia. Results: 120,677 BG values (mean n=302, 13.2±6.9 weeks’ duration) were obtained from 399 women (mean age 32.4±4.9 years, BMI 31.4±7.8 kg/m2, 36% European, gestation at GDM diagnosis 15.2±2.4 weeks’). Optimal glycemia was achieved in 72% of women; associated with reduced complications (95% BGs optimal: 23.6%, 90-95% optimal: 31.3%, 90% optimal: 45.5%; p=0.007). Complications were less in women with lower mean fasting glucose (MFG) (5.0 mmol/l: 17.1%, 5.0-5.2 mmol/l: 30.9%, 5.3-5.5 mmol/l: 25.6%, 5.6 mmol/l: 41.7%; p=0.009). Women with EGDM treated early (n=213) showed lower mean glucose (MG) and MFG compared with those treated late (n=116) (MG: 5.7±0.4 vs. 5.9±0.5, p0.001, MFG: 5.2±0.3 vs. 5.3±0.4; p=0.004), with greater optimal glycemia (95.9% vs. 93.8%, respectively; p=0.04). Similar findings were seen in the second and third trimesters. Conclusion: Early initiation of treatment in women with EGDM can improve subsequent maternal glycemia and reduce adverse pregnancy outcomes. Disclosure J. Immanuel: None. W. Hague: None. A. Sweeting: None. V.W.M. Wong: None. E. Hibbert: None. E.J. Gianatti: None. M.J. Peek: None. H. Teede: None. V. Mohan: None. N. Cheung: None. C.J. Nolan: None. A. Kautzky-Willer: None. J. Harreiter: None. H.E. Backman: None. D. Simmons: Speaker's Bureau; Abbott. Consultant; Sanofi. Speaker's Bureau; Ascensia Diabetes Care. Other Relationship; Ascensia Diabetes Care, Boehringer-Ingelheim. Research Support; Dexcom, Inc. Speaker's Bureau; Novo Nordisk. Research Support; Wests Club, NSW, Australia, Roche Diabetes Care. Funding National Health and Medical Research Council (NHMRC) (grants 1104231 and 2009326); Region Örebro Research Committee Dnr OLL-970566, OLL-942177; Medical Scientific Fund of the Mayor of Vienna, project 15205; South Western Sydney Local Health District Academic Unit grant 2016; Western Sydney University Ainsworth Trust grant 2019; Roche supplied glucose meters for the TOBOGM trial and provided access to the data.