Induction of the "pregnancy zone" protein by conjugated oestrogens

Abstract

Treatment with conjugated oestrogens was found to increase significantly the serum concentration of the pregnancy zone protein (PZ) in a group of postmenopausal women. The basic level of PZ before treatment was comparatively high in this group of women and might be related to age and previous pregnancies. Naturally occurring conjugated oestrogens have a similar effect on the induction of PZ as synthetic oestrogens.

PIP: The concentration of pregnancy zone (PZ) protein was measured by radioimmunoassay in postmenopausal women before and during treatment with conjugated estrogens (1.25 mg Promarit, 6 days/week for 2 months). The mean serum concentration of PZ in 34 women before treatment was 5.3 plus or minus .6 mg/100 ml. After treatment the mean serum concentration for 31 women was 13.9 plus or minus 1.7 mg/100 ml. The increase was significant (p less than .01). The level of PZ in these women was higher than usual and this is attributed to their age and to their previous pregnancies. Naturally occurring estrogens and synthetic estrogens have a similar effect on the induction of PZ.