A longitudinal study of maternal serum human chorionic gonadotropin levels during pregnancy

To determine if pregnant women with normal singletons will continue to have elevated serum human chorionic gonadotropin (hCG), given that they had an elevated serum hCG in the second trimester.

Nineteen women with second-trimester hCG levels > or = 2.0 multiples of the median, and 20 women with second-trimester hCG levels < 2.0 multiples of the median were the subjects of this investigation. All study participants had serum hCG levels repeated during the third trimester of pregnancy. We used a chi-square test and Student's t test for comparing categorical variables, and the means of continuous variables, respectively.

Using the criterion of > or = 2.0 multiples of the median of the comparison group to define hCG elevation, women with elevated second-trimester hCG levels were women with normal second-trimester hCG levels (risk ratio = 3.9; 95% confidence interval 1.6-9.8; p < 0.001). Adjustment for potential confounders did not materially alter the association.

Women with elevated hCG in the second trimester continued to have elevations in the third trimester. The persistence of elevated hCG levels in pregnancies uncomplicated by fetal anomalies should be evaluated as a clinical marker of adverse pregnancy outcomes.