Fran as an avid user of estrogen patches, I try to stay up on research. For every research that says cancer, another says no or only in much older women etc. Since I had to have a hysterectomy at age 40, and none of my siblings, mother or great aunts stopped their cycles until even mid 50s, it was very early. So like my specialist says, read the studies, decide on your own. The REAL dangers most agree on is uterine cancer, which I no longer have. And because mine was following years of fertility drugs, they took my ovaries too as very high risk related.
Okay so that said… not that I am aware. Hormones used on bitches has primarily been used only for 2 things-- urinary incontinence and to control cycles for showing. Some research has been done on its use in spay-related aggression issues, but not much. I think one issue is dogs live such short lives, by the time they would see results of hormones, the dog is dead. But they do know there were issues with the hormones used to control heat cycles, hence it is off the market in the USA. (checque drops were the common one I think-- someone can correct me if wrong).
