Combining human placental lactogen with routine glucose challenge tests.
Objective: To test the hypothesis that among gravidas with abnormal 1 hour glucose challenge tests (GCT), human placental lactogen (HPL) is higher for those found to have gestational diabetes.Study Design: Coincident with the GCT, serum was used to measure HPL by radioimmunoassay technique. Interassay and intraassay coefficients of variance were 6.0% and 1.4%, respectively. All GCT > 130 mg% were followed by a 100 g oral GTT (Carpenter criteria).Results: Two hundred fifty-seven women whose mean age was 29.4 years were studied. Twenty-two percent (57/257) had an elevated GCT. Forty-nine percent (25/57) of those with a positive screen were found to have an abnormal GTT. The mean HPL for this group of 25 women with gestational diabetes was 5.85 +/- 2.55 mg/mL and was significantly higher than the 3.38 +/- 1.40 mg/mL level in the 32 (32/57) women who had an abnormal GCT but a normal GTT, P =.034. The mean HPL for women who had a normal GCT screen was 4.68 +/- 1.64 mg/mL and was not statistically different from the HPL in women with an abnormal GCT but who had a normal GTT, P =.1. However, among the 11 women with a normal GCT but whose infants weighed >4000 g, the mean HPL was 5.83 +/- 1.29 mg/mL, which was similar to the mean HPL found in women with gestational diabetes.Conclusion: Our findings suggest that HPL levels are lower in groups of women with positive GCT but a negative GTT when compared to groups with a positive GCT but an abnormal GTT. Adjuvant HPL measurements may improve the positive predictive value of GCT.
Henderson
CE
Office of Research on Women's Health, NIH, Maryland, Bethesda, USA
Divon
MY