Aboriginal and Torres Strait Islander women experience a disproportionate burden of hyperglycaemia in pregnancy. A multi-component health systems intervention aiming to improve antenatal and postpartum care was implemented across Australia's Northern Territory (NT) and Far North Queensland (FNQ) between 2016 and 2019. Components included clinician education, improving recall systems, enhancing policies and guidelines, and embedding Diabetes in Pregnancy (DIP) Clinical Registers in systems of care. This program was evaluated to determine impacts on clinical practice and maternal health.Data for women with hyperglycaemia in pregnancy from primary care clinical records and the DIP Clinical Registers were analysed to assess changes in: antenatal and postpartum diabetes testing; HbA1c/glucose levels; medication use; weight checks performed, weight and body mass index; and postpartum contraception, smoking and breastfeeding.Clinical practice in the NT improved, including increased uptake of the recommended first trimester 75 g oral glucose tolerance test among women with hyperglycaemia risk factors (Aboriginal and Torres Strait Islander women 11.7% to 26.5%, p < 0.001; non-Indigenous women 6.2% to 19.3%, p < 0.001). In the NT, postpartum diabetes monitoring (56% to 68%, p = 0.039) and contraceptive use (41% to 60%, p = 0.001) increased among Aboriginal and Torres Strait Islander women. In FNQ, postpartum glucose monitoring increased among women with T2D (26% to 68% Aboriginal and Torres Strait Islander, p = 0.002; 50% to 100% non-Indigenous, p = 0.008), although there were no improvements in antenatal care indicators.Aspects of care for women with hyperglycaemia in pregnancy improved in the NT and FNQ following a multi-component health systems intervention.This study is funded by the Australian National Health and Medical Research Council (NHMRC) Global Alliance for Chronic Diseases Grant 1092968.