We surveyed members of National Association of Diabetes Centres (NADC) assessing use of new Australasian Diabetes In Pregnancy Society (ADIPS) and Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) Gestational Diabetes Mellitus (GDM) diagnostic guidelines in Australia. We found piecemeal adoption of recommended changes, with cessation of the 50 g glucose challenge test (GCT) universal, early screening implementation common, but by varied methodologies, and new diagnostic criteria acceptance far from complete with significant workload increases almost universal.