Diagnosis of pregnancy in marmosets: hemagglutination inhibition test and radioimmunoassay for urinary chorionic gonadotropin.

The Subhuman Primate Pregnancy Test kit was used for diagnosis of pregnancy in 17 marmosets. This hemagglutination inhibition test for urinary chorionic gonadotropin accurately indicated conception by positive responses in 72 and 76 specimens collected between the 4th and 10th wk following the estimated time of fertilization. The rate of false positive results did not exceed 1%. A radioimmunoassay system was used to quantify chorionic gonadotropin concentrations in urine. Detectable levels were present by the 2nd week of pregnancy. Peak chorionic gonadotropin levels were found between the 7th to 9th wk after conception. Chorionic gonadotropin excretion rates declined to undetectable levels during the final month of gestation.