GESTATIONAL DIABETES-MELLITUS - ANTENATAL VARIABLES AS PREDICTORS OF POSTPARTUM GLUCOSE-INTOLERANCE

Objective: To determine whether antepartum variables can predict postp artum glucose intolerance. Methods: Glucose tolerance was assessed 6 w eeks postpartum in 94 of 238 women with gestational diabetes using a 2 -hour, 75-g oral glucose tolerance test (GTT). Selected antepartum var iables were analyzed for predictive ability for postpartum glucose int olerance. Results: Of 238 patients, 94 (39%) returned for a GTT, Those returning and those not returning were similar in all variables. Post partum glucose intolerance occurred in 34%: impaired glucose tolerance in 18%, overt diabetes in 16%. No single maternal, intrapartum, or ne onatal variable was predictive of postpartum glucose intolerance in al l cases. Predictive variables included: requirement for insulin (insul in versus diet: 25 versus 3% impaired glucose tolerance, 26 versus 0% diabetes; P = .001), poor glycemic control (any P-hour postprandial bl ood sugar level of 150 mg/dL or higher: 34 versus 5% diabetes; P = .00 5), and the 50-g GTT value (200 mg/dL or higher: 32 versus 6% diabetes ; P = .01). For insulin requirement, the relative risk (RR) was 17.28 (95% confidence interval [CI] 2.46-121.45), and for the above three va riables combined, the RR was 19.68 (95% CI 2.88-134.42). When the insu lin dose was at least 100 U/day, all patients had abnormal glucose tol erance postpartum (RR 34.00, 95% CI 4.93-234.39). Conclusions: Postpar tum glucose screening is not warranted for women at low risk who do no t require insulin during pregnancy. The incidence of postpartum glucos e intolerance in this group is very low. Women with risk factors shoul d receive postpartum screening. Patients receiving at least 100 U/day of insulin have a 100% incidence of postpartum glucose intolerance.