The mean concentration of chorionic gonadotrophin in maternal serum at term was 9·45±0·93 I.U. per ml. and that of chorionic somatomammotrophin was 6·34±0·39 μg. per ml. In the amniotic fluid the levels were respectively 0·380±0·048 I.U. per ml. and 0·547±0·067 μg. per ml. In the cord blood serum mean values of 0·027±0·003 I.U. per ml. of HCG and 0·027±0·003 μg. per ml. of HCS were found. The barrier-effect of the amnion and placenta to the passage of these hormones is shown by the high ratio between concentrations in maternal serum (MS), amniotic fluid (AF) and cord blood serum (CS). The ratios between mean values (±SE) MS/AF and MS/CS for HCG is 41·62±3·49 and 440±46·33 respectively, while for HCS are 12·21±2·37 and 281±33·95 respectively. The transfer through the amniotic barriers of albumin, transferrin, IgG and HCS is inversely related to the molecular weight, while HCG crosses the membranes as in amounts proportional to IgG. The amniotic fluid concentrations of both these hormones are positively correlated with corresponding maternal serum concentrations. Significantly high maternal serum and amniotic fluid HCG concentration were found when the fetus was female than when it was male.
|Number of pages||5|
|Journal||The Journal of obstetrics and gynaecology of the British Commonwealth|
|Publication status||Published - Feb 1972|
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