The relationship of a prenatal one-hour plasma glucose screening and risk factors in a mixed population - abstract

ABSTRACT

A 50 gm prenatal one-hour plasma glucose challenge test was done on 158 mothers between 24 and 28 weeks' gestation to evaluate the relationship of this test with recognized risk factors and ethnicity. A value of 140 mg/dl or more was considered abnormal. Twenty-one (13.9 percent) had an abnormal result. When compared to those with normal values we found that a positive result was noted in 36.8 percent of mothers over 30 years old compared to 6.6 percent of mothers less than 30 years old (p<0.001). There was no significant difference between both groups with respect to parity and a family history of diabetes mellitus or hypertension. More women of East Indian descent (20.9 percent) had an abnormal result compared to those of African and Mixed descent (11.3 percent); but the difference was not significant (p<0.1). Fifty percent of the women who were over 30 years of age and of East Indian descent had a positive screen. The sensitivity and specificity of the risk factors - age over 30 years and being of East Indian descent - were 63.6 percent and 40.9 percent for sensitivity with the specificity being 82.4 percent and 75.0 percent, respectively. The 13.9 percent positive screening value is high in comparison to international figures. This screening test has a role in primary care obstetrics, but because of the potential cost limitations to testing all antenatal patients, we recommend that there is merit in initially confining screening to the above two risk groups in our population (AU)