Background: Current ADIPS guidelines recommend that all women with gestational diabetes mellitus(GDM) undergo follow-up oral glucose tolerance test(OGTT) at 6-12 weeks post-partum to assess for persistent abnormal glucose tolerance.1
Aim: To evaluate differences in characteristics of women with GDM who attended follow-up OGTT compared to those who did not.
Methods: We analysed prospectively collected data from 8102 singleton pregnancies affected by GDM (October 1991–April 2025) for rates of follow-up OGTT attendance. The differences between women who attended follow-up OGTT and those who did not were characterised using differences in means and independent sample t-tests for continuous variables, and odds ratios and chi-squared tests for categorical variables.
Results: A total of 3117(38.5%) woman with GDM attended follow-up OGTT. Table 1 shows differences in women who did and did not attend follow-up OGTT. Those who did not attend were younger, had higher pre-pregnancy BMI, higher HbA1c at diagnosis and greater pregnancy weight gain(all p<0.001). Furthermore, there were higher rates of pre-pregnancy obesity or overweight BMI, insulin use, large for gestational age or macrosomic babies(all p<0.001) and early GDM(p=0.034) amongst women who did not attend. Women of NZ/Pacific Islander(p<0.001), South Asian(p<0.001) and Middle Eastern(p=0.003) ethnicity were less likely to attend than women of Australian/European ethnicity. There were no differences in rates of overt diabetes in pregnancy (p=0.99) nor maximum insulin dose(p=0.71) between the groups.
Conclusion: Rates of post-partum OGTT attendance amongst GDM women are low. Concerningly, those who did not attend were more likely to have risk factors for persistent glucose intolerance.