Germanicanus: @Xohan:
Dryads are not humans. I don't think druids and mages use magic on the same level. Though we hardly meet any druids in the novels (and those who we meet tell us absolutely nothing about their abilities), one of the most powerful mages happen to be taught by druids - and ridiculed it to a great extent. In the canon druids can use only elemental magic, and despite having a much longer life-span than humans, do not posses as vast amount of skills as typical mage. Elven Blood is, as the name suggests, elven, so it has nothing to do with human mages. Francesca Findabair, one of the few Elven Sorceresses from the books, said she is unable to bear a child due to her old age (more than hundred years old), so she wasn't infertile.
Nenneke, the healer and priestess of Melitele, said Yennefer is infertile because of irreversible damage of gonads. It's fair to conclude that some human sorceresses cannot use magic without making themselves infertile. However, those who can, produce a very weak, mentally ill offspring. Since an unstable source cannot control magic, they are dangerous to the others and have to be eliminated. This is why Tissaia de Vries decided to make all sorceresses sterile. There is no hint, no suggestion or even not a single word about "beauty treatments" being responsible for it.
P.S. I don't think we can call Calanthe or Pavetta a sorceress before defining this term. If it means a woman capable of using magic, every female druid, witch or priestess are automatically sorceresses. In my opinion, it's better to assume a sorceress is a female competent and educated in the use of magic, in either one of magic academies like Aretuza, or by other mage. In the books a druid or priest is never called a mage.
I agree. I think in "Something More" it says that only younger elves are re-productive (when Ciri and Geralt was visiting the ruins of Sherrawedd). Also, I think I read in Blood of Elves (probably Triss said it in Kaer Moehn) that most sorceress are infertile because the use of magic alters the body that it disrupts its natural function, while the rest are made infertile (in magic schools) because they give birth to unstable magic-users.