Screening for abnormalities of carbohydrate metabolism in pregnancy 1966-1977: the Belfast experience

Of the 30,300 mothers who attended consecutively at the antenatal clinic during an 11-yr period, 3063 mothers screened positive using clinical criteria for potential diabetes in pregnancy. These 3063 mothers had a glucose tolerance test (GTT), of which 661 were judged abnormal. At different times an oral GTT, cortisone-stressed GTT, or i.v. GTT were used and several changes in the clinical screening criteria and interpretation of the GTT values were made. There was a steady fall in fetal loss in all groups of mothers during the period. Those mothers whose glucose intolerance was between one and three standard deviations above the mean had only slightly more pregnancy complications than those with a normal GTT. Apart from clicnial recognition of this state, no special management of these mothers was necessary. Long-term decompensation of glucose tolerance to frank or symptomatic diabetes was uncommon.