Gestational Diabetes Mellitus (GDM)

The prevalence of Gestational Diabetes mellitus (GDM) is growing worldwide. 1-14% of women in pregnancy is affected by DM 1. Due to increased incidence and proposed lower¬ing of the thresholds for diagnosis the health care cost of GDM can be expected to rise proportionately. The discussion of whether a benefit exists to the treatment of GDM assumes greater importance now than in the past.

Even though it has long been known that women with preexisting type 1 and type 2 diabetes are at increased risk for adverse maternal and fetal outcomes, the relationship of GDM to various perinatal risks has been less clear. O'Sullivan and Mahan3 developed, Glucose tolerance test criteria for the diagnosis of GDM, nearly 50 years ago. It has been known that, if optimal care is not provided, women with GDM and elevated fast¬ing glucose levels appear to be at risk for fetal overgrowth and perinatal morbidity.4

For several decades whether a significant association of milder forms of carbohydrate intolerance exists with macrosomia and adverse perinatal outcomes has been questioned and debated.5 Older studies, focusing on this issue interpreted that confounding variables including parity and maternal obesity may not have been considered in the analyses or that treatment was in fact applied to the population described.6 . Therefore, the effect of glycemia on various outcomes may have been incorrectly estimated.

The recent Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study has settled much of the debate about the relationship of various degrees of maternal glycemia to specific pregnancy outcomes.7 In this large-scale international study, women with fasting glucose up to 105 mg/dL, were enrolled. The researchers described the continuo...

... middle of paper ...

...at new diagnostic thresholds

based on relative risk must be adopted by

expert consensus.

Frequency of LGA infants and primary cesarean rates as seen in HAPO study is given in table 2.

Evidence of any benefit to the treatment of glucose levels lower than the current criteria for diagnosis are lacking. Studies seen above provide evidence that treatment of even

mild GDM with dietary intervention and insulin as necessary is effective.

The need to establish such clinical evidence cannot be ignored because it affects the perception of health care advisories who consider the merits of treating the full spectrum of GDM. In an

era when evidence-based medical practice should be a guiding principle, GDM can finally now be considered an entity for which recommendations can be based on data derived from clinical trials rather than on solely expert opinion.