In the early 20th century, they used to extract CEEs from pregnant mare urine for HRT. And now we have all the cool modern stuff. Here is a Wikipedia article to get started. I also recommend researching ancient transgender history for more info since it is really interesting.
Context for a young transfem?
Here’s a kind of explanation of the folklore around it: https://talesoftimesforgotten.com/2022/06/03/no-ancient-skythian-enarees-didnt-drink-urine-from-pregnant-mares-as-a-primitive-form-of-hrt/
In the early 20th century, they used to extract CEEs from pregnant mare urine for HRT. And now we have all the cool modern stuff. Here is a Wikipedia article to get started. I also recommend researching ancient transgender history for more info since it is really interesting.