MATERNAL GLYCOMETABOLIC OPTIMIZATION AND PREGNANCY OUTCOME IN GESTATIONAL DIABETES-MELLITUS

Intensive management protocols, based on very low glycemic targets, ha ve been proposed in recent years for gestational diabetes mellitus (GD M), Doubts still exist, however, about an approach centered exclusivel y on maternal glycometabolic optimization, also because of possible ri sks of fetal growth retardation. In order to evaluate how different de grees of maternal glucose control can influence pregnancy outcome, we re-evaluated obstetrical and perinatal results of 142 GDM women treate d with one of two therapeutic schemes, characterized by different glyc emic goals. In a first group (A) of 71 women (age 31.5+/-5.0 yr, BMI 2 5.4+/-4.8 kg/m(2)), conventional glycemic goals (100 mg/dl fasting, 12 5 mg/dl postprandial) were adopted, whereas from 1993 on targets were lowered to 90 mg/dl fasting, 120 mg/dl postprandial, in a second group (B) of 71 age and BMI-matched GDM women; a control group of 71 random ly selected negative screenees was also considered. Glycemic concentra tions well within the target range were obtained in Group A, with diet in 83.1%, and insulin in 16.9%; however, the incidence of large for g estational age (LGA, greater than or equal to 90(th) centile) was sign ificantly higher (22.5% vs 9.9%) than in controls. The metabolic optim ization obtained in Group B (fasting/postprandial glycemia 82.4+/-13.6 / 101+/-18.2 mg/dl, p<0.001 vs A) was followed by a modest lowering o f LGA rate (19.7% vs 22.5%); the higher rate of newborns less than or equal to 10th weight centile found in Group B (12.7% vs 1.4%) was not attributable to low glycemic levels, while a relationship may be hypot hesized with maternal weight gain during pregnancy. We conclude that e ven the very tight maternal metabolic control obtainable with glycemic targets as low as 90/120 mg/dl only partially succeeds in improving p regnancy outcome in GDM, A further indiscriminate lowering of maternal glycemic concentrations seems, at present, not justified; the objecti ve of a full normalization of fetal overgrowth probably requires alter native approaches, integrating maternal and fetal parameters in determ ining therapeutic decisions, (C) 1998, Editrice Kurtis.