Uterine fluid and prolactin secretion in the ovulating cynomolgus monkey.

Immunoreactive prolactin is produced by late secretory human endometrium in vitro. Human myometrium in explant culture also produces prolactin. A primate model with the use of the cynomolgus monkey is described that allowed repeated samplings of uterine secretions in vivo. The uterine secretory prolactin thus measured appears immunoreactively similar to human serum prolactin, and the pattern of secretions reflects the previously described pattern of endometrial prolactin production in vitro.