One asked me to prepare a cream with progesterone 3%. Is there an ideal base?

I suspect that an absorption into the bloodstream of the progesterone   is expected. This will be difficult to achieve with cetomacrogol cream. You can cut two other possibilities:

1. Use a PLO gel;   The composition can certainly be found on the Internet and also on the question box. But not only the gel is no longer sold by Bassron, also the constituents such as the indispensable lecithin.  

2. Use Pentravan, an ointment base sold by Bassron; it is claimed that it brings the medicine deep into the skin.  

The first possibility would allow you to prepare a quantity as much as necessary for the execution of the prescription. From Pentravan you will have to buy a pack and you will be left with surplus. If you can count on renewals of this regulation, you will be able to gradually rework the contents of the pot.

In The commentary The alternative is described, which I developed for the PLO gel. Treatment with the Unguator has a beneficial effect on color and texture.