At a time when non-oral estrogens are easily available I cannot understand why anyone would take oral estrogens again, for feminization or even for menopause.

Oral estrogens should be vigorously avoided in trans-women.

Oral estrogens must pass through the liver before entering the systemic circulation of the body. As a result much of this estrogen is excreted only to be reabsorbed through the "entero-hepatic circulation". As a result the liver is selectively overdosed with estrogen. Because the liver is not an indifferent conduit thanks to the fact that it is rich in estrogen receptor alpha, overdosing it with estrogen can be dangerous and side-effect laden. Oral estrogens selectively increase sex hormone binding proteins thus limiting the availability of estrogen to its target tissues. At the same time oral estrogens increase the risk of clotting, gallbladder disease, elevated triglycerides, pancreatitis, edema, hypertension, fatigue and depression due to diminished brain estrogen levels. The clotting problem alone can lead to stroke, heart attack or sudden death. To sum up the oral route for hormones offers the greatest risks and side effects and the least feminizing benefits. Nevertheless the vast majority of transgender patients in this country obtain their estrogen in an oral form either from the Internet or from practitioners lacking knowledge in the field of endocrinology and practicing beyond their scope of expertise.