How are commercial steroid hormones produced?
In this recent review you can find fascinating information on all aspects of this topic. It's dense in sterol structures and chemical interconversions, but that's what you have to expect. This is my pr&eacute;cis.

Direct isolation from primary biological sources This was the heroic phase of research in this area: 


  Androsterone was first isolated from the urine of policemen. Quickly, however, it became evident that natural isolation of hormonal steroids would not satisfy the demand, as, for instance, in 1931, 15,000 L of urine yielded only 15 mg of pure androsterone. Similarly, 4 tons of sows' ovaries were needed to isolate 12 mg of estradiol, while extraction from 625 kg of sows’ ovaries produced 20 mg of progesterone. 


[edited by removal of citations]

There are still some commercial processes in this class: 
Premarin contains estrogens produced from the urine of pregnant mares.

Chemical transformations starting from steroidal sapogenins of Dioscoreae (yam) These processes still make a contribution but there is a limiting availability of the starting plant material. Apparently important in China.

Direct total synthesis
This section describes chemical routes, but there don't seem to be any commercial processes

Chemical synthesis from cholesterol and phytosterols Phytosterols are plant sterols, available from e.g. soy bean oil, rape seed and paper pulp industrial waste. They can be chemically converted to steroid hormones, as described in the review, but there don't seem to be any commercial processes.

Microbial conversion of phytosterols
Bacteria can convert plant sterols into useful products. Mycobacteria seem to be particularly useful.


  Today, more than 1000 tons of steroids are produced annually from phytosterols by microbial transformation, alone.