1. Can be administered orally, transdermally, subcutaneously, or vaginally
2. Best estradiol; estrone ratio is achieved through implants (6 months)
3. List of estrogen types: estradiol, estriol, estrone, estropipate, estradiol valerate, conjugated equine estrogen
4. Estrogen alone may be used if the patient had undergone hysterectomy