If sleep apnea is an issue, take care you're not blocking estrogen too much. Estradiol and progesterone both help apnea, but estradiol seems to be a particularly key player. There are cases of people developing sleep apnea due to aromatase inhibitors, cases of FtM transexuals developing apnea on estrogen blockers, and a case of at least one MtF on estradiol alone resulting in complete resolution of severe obstructive sleep apnea.