Radioimmunoassay of human chorionic gonadotropin: Serum profile, circadian urinary excretion, and clearance values in pregnancy

Pier Giorgio Crosignani, Bruno Brambati, Torquato Nencioni

Research output: Contribution to journalArticle


HCG concentrations were measured in the sera of 47 healthy women at different stages of pregnancy; 29 I.U. ± 4.1 S.E., 11.2 I.U. ± 4.3 S.E., and 13.6 I.U. ± 2.2 S.E. are the serum values found, respectively, in the first, the second, and the third trimesters of gestation. Serum HCG levels observed over a period of 72 hr. appear stable. It was not possible to demonstrate any circadian rhythm in HCG urinary excretion. HCG urinary concentrations and outputs derived from intraday and interday findings appear extremely variable. Nevertheless, high significant correlation has been found between HCG concentration in the first morning urine and HCG 24 hr. urinary output. The HCG clearance values found in the first, second, and third trimesters are, respectively: 0.94 ± 0.27 S.E., 0.66 ± 0.11 S.E., and 0.85 ± 0.10 S.E.

Original languageEnglish
Pages (from-to)985-990
Number of pages6
JournalAmerican Journal of Obstetrics and Gynecology
Issue number7
Publication statusPublished - Apr 1 1971


ASJC Scopus subject areas

  • Medicine(all)
  • Obstetrics and Gynaecology

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