The Bernese Gestational Diabetes (GDM) Project: Postpartum Oral Glucose Tolerance Test (OGTT) in women after gestational diabetes
20 September 2018 (online)
The incidence of GDM is increasing worldwide. The aim of this study was to examine the adherence of our cohort to postpartum (pp) screening by 75 g OGTT and to determine the incidence of abnormal glucose metabolism.
Material and methods:
Women were recruited from a prospective cohort study investigating the role of first trimester GDM screening by HbA1c. Secondary outcomes of this study were the incidence of postpartum dysglycaemia. The adherence to pp screening as well as incidence of abnormal pp OGTT were investigated. Furthermore, the association between first trimester HbA1c and OGTT was analysed. Women with pre-gestational diabetes or HbA1c ≥6.5% were excluded. Parametric and non-parametric tests were used for statistical analysis.
From 2014 to 2016, 205 women were diagnosed with GDM. 108 (52.7%) underwent pp OGTT (88 ± 52 days pp). 9 (8.3%) women were excluded and 23/99 (23.2%) had abnormal screening results. Incidences of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), IFG and IGT, or diabetes were 10%, 7%, 3%, and 3%, respectively. Women with pp dysglycaemia had higher first trimester HbA1c than those with normal OGTT (5.43%± 0.34 vs. 5.25%± 0.34; p = 0.01).
The lack of adherence to pp screening is concerning regarding the high incidence of dysglycaemia in our cohort. In view of the potential for early prevention of DM, strategies to increase the pp testing-rate should be evaluated. The correlation with first trimester HbA1c will be further investigated.