Aims: To investigate whether systemic inflammatory indices and the last trimester APRI score change in PGDM and to evaluate the relationship between these alterations and perinatal outcomes.

Methods: A total of 240 pregnant women, 120 of whom were pregestational diabetic (40 with T1DM and 80 with T2DM), were analyzed. In each trimester, WBC, NEU, LNF, PLT, NLR, dNLR, PLR, PNR, and SII values, and in the last trimester MON, PMR, SIRI, AST values, and APRI score were recorded and compared between PGDM and control cohorts.

Results: The first trimester WBC, NEU, and LNF values were higher and the PNR values were lower, the second trimester LNF value was higher and the NLR was lower, the third trimester APRI score was higher in the PGDM group. In diabetic pregnant women, the optimal cut-off value of NEU for predicting LBW in the first trimester was 6.965 × 10⁹/L (62.5% sensitivity and 61.6% specificity), while the optimal cut-off value of the last trimester APRI score for predicting preterm delivery was 0.072 (61.9% sensitivity and 61.6% specificity). In predicting NICU, the optimal cut-off value for second trimester NLR was found to be 3.973 (70% sensitivity and 70% specificity) in the T1DM group, while the optimal cut-off values for first and second trimester LNF were 2.395 × 10⁹/L (75% sensitivity and 71.1% specificity) and 2.23 × 10⁹/L (75% sensitivity and 68.4% specificity) in the T2DM group, respectively.

Conclusions: In routine clinical practice, the first trimester NLR and last trimester APRI score may be used as additional tools for predicting perinatal outcomes in pregnancies affected by PGDM.