Trophoblast Production of hCG and αhCG from Normal and Abnormal Pregnancies

Abstract

This study was designed to correlate early pregnancy outcome with serum and trophoblastic culture media levels of hCG, ΑhCG, and the ΑhCG/hCG ratio. Maternal serum was obtained from 104 women with normal gestations (n = 25), ectopic pregnancies (n = 43) and spontaneous abortions (n = 36); trophoblastic tissue was obtained from 10 subjects in each group. The ΑhCG/hCG ratio was abnormally elevated in the serum of 46% of women with abortions and 26% of those with ectopic pregnancies. Tissue culture experiments confirmed the relative increase in ΑhCG levels. Deteriorating trophoblast tissue from compromised or poorly oxygenated placental implantations results in abnormally elevated ΑhCG/hCG ratios; this occurs secondary to a greater relative decrease in hCG than ΑhCG production. The clinical utility of this knowledge is under investigation.