The Australasian Diabetes in Pregnancy Society (ADIPS) recommends testing for gestational diabetes mellitus (GDM) at the first available antenatal opportunity for women with acknowledged risk factors. The method of testing is at the discretion of the obstetric care provider. The fasting glucose level will normally fall after the first trimester and it is possible that women with an abnormal result may be normal if tested later in pregnancy. Our clinical impression is that many more women than expected are being referred for the management of GDM after a raised fasting glucose level in the first trimester. The purpose of this audit was to determine how many women were being tested according to the ADIPS guidelines.
Methods.
All of the women with GDM referred to the Diabetes Centre in Wollongong for the last 6 months of 2015 have been considered. Referrals were from general practitioners, antenatal clinics and private obstetricians. The obstetric population has an ethnic distribution similar to national data.
Results.
There were 444 women referred with GDM of whom 139 had a GTT after 20 weeks and have not been considered further. There were 301 women with singleton pregnancies tested before 20 weeks with a fasting glucose. Risk factors considered were; non-Australian country of birth 28 (9.3%), previous GDM 56 (18.6%), family history 72 (23.9%), maternal age ≥ 40 12 (4.0%), BMI > 30 (99) (32.8%). Overall 190/301 (63.1%) had one or more risk factors. Women with risk factors were more likely to require insulin therapy (OR 1.98. p = 0.02).
Conclusion.
Around 40% of the women being tested early in pregnancy had no risk factors, but some still subsequently met the criteria to commence on insulin. Fasting glucose levels used for diagnosis in early pregnancy are still an area of contention.