In the context of a global obesity and diabetes epidemic, gestational diabetes mellitus and other forms of hyperglycaemia in pregnancy are increasingly common. Hyperglycaemia in pregnancy is associated with short and long term complications for both the woman and her baby. These 2025 consensus recommendations from the Australasian Diabetes in Pregnancy Society (ADIPS) update the guidance for the screening, diagnosis and classification of hyperglycaemia in pregnancy based on available evidence and stakeholder consultation.Overt diabetes in pregnancy (overt DIP) should be diagnosed at any time in pregnancy if one or more of the following criteria are met: (i) fasting plasma glucose (FPG) ≥ 7.0 mmol/L; (ii) two-hour plasma glucose (2hPG) ≥ 11.1 mmol/L following a 75 g two-hour pregnancy oral glucose tolerance test (POGTT); and/or (iii) glycated haemoglobin (HbA) ≥ 6.5% (≥ 48 mmol/mol). Irrespective of gestation, gestational diabetes mellitus should be diagnosed using one or more of the following criteria during a 75 g two-hour POGTT: (i) FPG ≥ 5.3-6.9 mmol/L; (ii) one-hour plasma glucose (1hPG) ≥ 10.6 mmol/L; (iii) 2hPG ≥ 9.0-11.0 mmol/L. Women with risk factors for hyperglycaemia in pregnancy should be advised to have the HbA measured in the first trimester. Women with HbA ≥ 6.5% (≥ 48 mmol/mol) should be diagnosed and managed as having overt DIP. Before 20 weeks' gestation, and ideally between ten and 14 weeks' gestation, if tolerated, women with a previous history of gestational diabetes mellitus or early pregnancy HbA ≥ 6.0-6.4% (≥ 42-47 mmol/mol), but without diagnosed diabetes, should be advised to undergo a 75 g two-hour POGTT. All women (without diabetes already detected in the current pregnancy) should be advised to undergo a 75 g two-hour POGTT at 24-28 weeks' gestation.These updated recommendations raise the diagnostic glucose thresholds for gestational diabetes mellitus and clarify approaches to early pregnancy screening for women with risk factors for hyperglycaemia in pregnancy.