(1249) Timing of Diabetes Diagnosis and Perinatal Outcomes: A Secondary Analysis of the MOMPOD trial

Objective:
ACOG and ADA recommend screening for undiagnosed pregestational diabetes (DM) at the first prenatal visit, but it is unclear if outcomes differ based on timing of DM diagnosis. Our objective was to compare outcomes in pregnant patients with type 2 DM diagnosed before pregnancy and in early pregnancy.

Study Design:
Secondary analysis of a randomized controlled trial of metformin for insulin-treated type 2 DM in pregnancy. We included participants with data on diagnosis timing, initial HbA1c and the neonatal composite (Table 2). Baseline characteristics and outcomes were compared between those with DM diagnosed before pregnancy versus during pregnancy < 23 weeks. We used HbA1c-matched conditional regression, propensity score matching and multivariable logistic regression to adjust for confounding.

Results:
Of 686 eligible participants, 428 were included in the HbA1c-matched cohort: 111 (26%) diagnosed during pregnancy and 317 (74%) before pregnancy. Mean HbA1c was 7.2±1.6% (range 4.8-12.4%) with no difference between groups after matching (Table 1). Compared with diagnosis before pregnancy, participants diagnosed during pregnancy enrolled at a later GA and had lower baseline insulin doses (Table 1). The neonatal composite was similar between groups (58% v 69%; aOR 0.61, CI 0.37-1.01). Diagnosis during pregnancy was associated with lower odds of low birthweight and NICU admission (Table 2). Similar findings were observed with propensity score matching (1⁰ outcome aOR 0.66, CI 0.43-1.00), traditional multivariable regression (aOR 0.62, CI 0.37-1.02) and after restricting to patients diagnosed during pregnancy by HbA1c or fasting glucose (aOR 1.01, 95% CI 0.53-1.90).

Conclusion:
In a large, diverse cohort we found that neonatal morbidity was similar among those with preexisting DM and DM diagnosed in early pregnancy after accounting for baseline HbA1c, underscoring the importance of DM screening in early pregnancy. Although low birthweight and NICU admission may be less common with DM diagnosed in pregnancy, patients may benefit from similar counseling and care as those diagnosed preconception.