GESTATIONAL DIABETES - A CHALLENGE FOR THE FUTURE

It is well established that pregnancy is associated with temporary cha nges in maternal metabolism which include a decrease in maternal insul in sensitivity to values similar to those associated with Type 2 diabe tes.(1) Fasting glucose concentrations fall throughout pregnancy, post prandial values rise.(2) The maintenance of glucose tolerance in pregn ancy requires a two- to three-fold increase in postprandial maternal i nsulin secretion.(1-3) Clucose intolerance develops in women unable to compensate for the metabolic changes incurred by pregnancy. Increasin g maternal hyperglycaemia is associated with increasing pregnancy morb idity(4,5) and an increased likelihood of subsequent diabetes in the m other.(6-8) In addition, maternal hyperglycaemia has a direct effect o n the development of the fetal pancreas and is associated with an incr eased susceptibility to future diabetes in the infant, an effect which is independent of genetic factors.(9) Gestational diabetes mellitus ( GDM) is defined as glucose intolerance first recognized in pregnancy, and by definition includes a small number of women with previously unr ecognized diabetes or impaired glucose tolerance (IGT).(10) Figures on the prevalence of GDM vary between maternity units, depending on scre ening methods and the ethnic distribution of the populations. However, in a comprehensive study of a multi-ethnic antenatal population in in ner London, UK it was found that only 2 % of pregnant women develop si gnificant glucose intolerance.(11) (12) Obstetricians physicians debat e the importance of identifying this 2% of women.(13-15) The lack of a greed criteria for diagnosing gestational diabetes(16) and the questio nable obstetric benefits of treating all women with mild disturbances of glucose tolerance in pregnancy has resulted in few UK centres under taking universal screening for GDM. This review examines the potential benefits arising from the diagnosis of gestational diabetes, both for pregnancy outcome in the short term and for the health of the mother and child in the long term.