AIM: To determine the prevalence of depression and anxiety during pregnancy and its association with GDM. METHODS: A total of 2141 pregnant women were recruited before 16 weeks of gestation (mean gestational age: 10.5 ± 2.9 weeks) from the STRiDE study in south India. Early GDM (eGDM) was detected in the first trimester, and late GDM (lGDM) during 24-28 weeks, both diagnosed using IADPSG criteria. Depression and anxiety were assessed using the PHQ-9 (score≥10) and GAD-7 (score≥7) scales, respectively. RESULTS: Overall, 14.9 % had depression and 17.5 % had anxiety in early pregnancy. eGDM was diagnosed in 474 (20.4 %) and lGDM in 321 (19.3 %) women. Women with eGDM had higher prevalence of depression (20.9 %) than those with lGDM (15.6 %, p = 0.06) and those without GDM (13.3 %, p <
0.01). Anxiety was also higher in eGDM (21.1 %) compared to IGDM (15.3 %, p <
0.05) and women without GDM (16.6 %, p <
0.05). eGDM was significantly associated with depression (aOR=1.84, 95 % CI:1.37-2.47, p <
0.001) and anxiety (aOR=1.36, 95 % CI:1.03-1.79, p = 0.03) after adjusting for age, systolic blood pressure, BMI, socioeconomic status, and family history of diabetes. CONCLUSION: Women with early GDM have a higher prevalence of depression and anxiety compared to those with late GDM and women without GDM. Early and universal screening for GDM should be done and its association with mental health wellbeing should be explored and supported.