Pyometra in the dog. III.--A pathophysiological investigation. III. Plasma progesterone levels and ovarian morphology.

The peripheral plasma progesterone levels in bitches with spontaneously developed pyometra did not differ significantly from those in normally cycling or pregnant bitches. The macroscopic ovarian morphology gave no indication of an increased corpus luteum activity. Ovarian follicular cysts were found in 4 out of 31 cases. There was no detectable difference of results between 14 bitches that had received hormonal medication 10 years to 1 week previous to the pyometra diagnosis, and the other patients.