SERUM AND URINE INSULIN IN LATE PREGNANCY AND IN A FEW PREGNANT LATENT DIABETICS

Abstract

SUMMARY: As measured both by immunoassay and bioassay during a glucose tolerance test (50 g.) on ten subjects in the third trimester of pregnancy, the serum insulin levels fasting, 1 and 2 hr. after glucose were raised at least threefold compared with the levels in 23 non-pregnant women. The renal clearance of immunoassayable insulin was lower than that in the non-pregnant state (the mean in the pregnant subjects was 0·18 ml./min. compared with 0·45 ml./min. in the normal non-pregnant subjects). In the same subjects the mean serum non-suppressible insulin-like activity, which is unaltered by oral glucose, was 1·5 times higher than the non-pregnant mean level, but this difference was not significant. Four pregnant latent diabetics, tested similarly in the latter part of pregnancy, showed even higher fasting serum insulin levels than the normal pregnant subjects, but a lessened response to the same glucose load.