[prettylily]

I haven't tried PM, but introducing an outside estrogen source to the body might cause the body to produce less, so when you stop/develop a tolerance, your estrogen levels would go down. Like long-term drug addicts end up with really low levels of seratonin because they've flooded their receptors with artificial seratonin (obviously a negative example, but I couldn't think of another one).

Just my thoughts! Also, I think there's a lot of hype around PM, and with hype comes misinformation.