[Measurement of plasma oxytocinase. Comparison with urinary excretion of estrogens]

Plasma cystinylaminopeptidase (CAP) activity and 24 h urinary excretion of oestrogens were measured simultaneously in 102 pathological pregnancies. The correlation between the two chemical assays is weak (p = 0,13, to 0,47). Plasma CAP levels were significantly (p less than 0,01) lowered in cases of fetal death; but urinary oestrogen assays were within the normal limits (p greater than 0,1) in this group. Each assay suggested an equal number of correct or incorrect prognoses. Their association resulted in 9 correct prognoses in 12 pregnancies with unfavourable outcome, but led to 12 unduly bad prognoses in a group of 40 normal births. The association of the two assays allows a more adequate diagnosis of high-risk pregnancies, but has the disadvantage of offering an unduly bad prognosis in a greater number of normal cases.