Wrong test used to diagnose diabetes following pregnancy

Experts suggest that the NICE guidelines for diagnosing forms of diabetes in women, following a term of gestational diabetes, recommends the wrong test.
The study, presented at Diabetes UK’s Annual Professional Conference in Glasgow, suggests that cases of post delivery diabetes are being missed because the test used to diagnose diabetes is not the most appropriate.
Gestational diabetes is a type of diabetes that specifically develops during the term of pregnancy but can persist afterwards. Currently, at six weeks after pregnancy, a fasting blood glucose test is taken to diagnose a persistence in abnormal glucose metabolism. The study presented at the conference, however, advises using an oral glucose tolerance test (OGTT) instead.
The study involved a review of just under 150 women which had gestational diabetes. The women in the study were given both the fasting blood glucose test and the OGTT test. If just a fasting glucose test had been performed one of the eight women diagnosed with type 2 diabetes would have been missed and none of the 21 women with impaired glucose tolerance would have received a diagnosis. In comparison, if only an OGTT was performed, 16 out of 23 cases of impaired glucose tolerance would have been missed.
The study highlights limitations of a fasting glucose test for diagnosis, but experts are not in agreement that an OGTT is the best replacement. An annual HbA1c test was cited by experts as an alternative, and potentially better, diagnostic test.