Urinary chorionic gonadotrophin determination.

Successful laboratory tests for early pregnancy utilize the endogenous production and excretion of chorionic gonadotrophin (CG). There is wide variation in sensitivity and specificity of various biological and commercially available immunochemical methods for determining urinary CC levels. Normal values for immunochemically reactive CC during the first trimester of pregnancy are given. Serial determinations of CC have diagnostic value in assessing various abnormal pregnancy states. An abnormally increased urinary output of CC is observed in some neoplasms-e.g., chorionepithelioma, and a rapidly rising CC level is strongly suggestive of molar pregnancy. Urinary CC levels falling below the normal range may indicate an ectopic pregnancy or an inevitable, incomplete, or “missed” abortion. The immunochemical CC determination also offers a sensitive, simple, and convenient routine method for following patients who have been treated for hydatidiform mole or chorionepithelioma.