Just a note about names at this point, because there is a fair amount of confusion about what to call these synthetic substances. Just be aware if you see any of the other names that they are referring to exactly the same group of substances. There is only one progesterone-the natural substance. The progestins so widely prescribed are synthetic substances derived from minute amounts of botanical source materials. They mimic some of progesterone's functions, and they have some advantages for particular applications, but all of them are chemically different from progesterone.
Progestins have some limited advantages.
They are administered orally, which makes them convenient to take. Further, the oral tablets facilitate specific and consistent dosage, making them convenient to prescribe. That's both good news and bad news. The good effects persist, but so do the unwanted ones. Side Effects of Provera tm The question of side effects is not to be taken lightly.