All my life, I've been sensitive to how fluctuations in Estrogen affected me. I could not take hormonal birth control because it was either too much or too little. When I got hormone receptive breast cancer, had my ovaries removed my body revolted. I could not take full strength hormone for risk of the cancer returning and because it would be too strong (I was on it briefly). Without compounding, finding the right dose for me is not an option.