Serum levels of human chorionic gonadotropin (hCG) were measured in venous blood samples of 100 healthy pregnant Nigerian women from weeks 5 to 40, using a batasubunit, hCG--specific radioimmunoassay. By week 5 hCG concentration was 3.39 +/- 2.35 Iu/ml (mean +/- SEM). An exponential rise occurred from week 5 to 8, during which period a direct relationship was observed between serum hCG levels and the gestational age (r2 = 0.996; p less than 0.001). The calculated mean doubling-time of hCG concentration, during this period of exponential increase was 5.08 days. A peak hCG concentration of 62.61 +/- 0.81 Iu/ml was attained at week 8, followed by a progressive decrease in concentration from week 9. The decrease in concentration reached a nadir by week 17 with a value of 4.77 +/- 2.48 Iu/ml. Between weeks 17 and 40 no significant difference in weekly mean values was detected. The respective mean values of hCG for the three trimesters were 25.79 Iu/ml for the first (n = 32), 8.91 Iu/ml for the second (n = 86) and 5.18 Iu/ml for the third (n = 110). There was no secondary peak of hcG concentration during the third trimester. The significance of these data is discussed.
|Number of pages||8|
|Journal||West African Journal of Medicine|
|Publication status||Published - Jan 1989|