In the "Treatment Option Considerations
Steroid Profiles in the Diagnosis of Atypical Cushing’s Disease
Clinical Endocrinology Service/College of Veterinary Medicine/University of Tennessee" (http://www.vet.utk.edu/diagnostic/en...ushing%27s.pdf
)
NOTE:
Trilostane always increases 17-hydroxyprogesterone (some cross-reactivity with pregnenolones in
assays??), and frequently increases estradiol and androstenedione as well. LysodrenTM may be
preferred for Atypical Cushing’s cases.
Trilo reduces cortisol, progesterone and aldosterone but increases 17-hydroxyprogesterone and often increases estradiol and androstenedione as well. This is because of the way it interrupts the synthesis of the adrenal steroids and also might be related to the adrenal hyperplasia that can occur after several months of Trilo treatment particularly when the dog has PDH (which is usually why it is being used).

So it looks from that info that Palmers elevation of progesterone is probably not as a result of the Trilo. The way that Trilo interefers with progesterone production is the biggest reason that Trilo should not be handled by a pregnant woman.

Alison