The relation between pregnancy specific beta 1 glycoprotein (SP1) levels and abnormal glucose tolerance in pregnancy.

Pregnancy specific beta 1 glycoprotein (SP1) levels were measured in 54 potentially diabetic patients in the third trimester of pregnancy using a laser nephelometric method. All patients were tested by the 50 g oral glucose tolerance test. The results show that a significantly greater number of patients with abnormal glucose tolerance had SP1 levels above the mean compared with patients with normal glucose responses. All patients with a diabetic type response had SP1 levels above the mean. There was no significant difference in SP1 levels in the fasting and two-hour plasma samples. The study suggests that patients with asymptomatic glucose intolerance in pregnancy have higher SP1 levels than patients with normal glucose tolerance. It is possible that one of the factors controlling the placental output of SP1 is the maternal blood glucose level.