Confused about AIs and SERMS

Hi,
I've been reading this thread http://forums.steroid.com/pct-post-cycle-therapy/94545-serm-ai-definition.html and something struck me (not literally)! If a AIs like Proviron totally prevent the conversion of androgens into estrogen then why is it necessary to also take SERMS like Nolva during a cycle. IF there's no increase in estrogen because of the Proviron then why take a SERM? :scratch:

Hope this doesn't sound too stupid a question...

THanks
Schwarz

Not a stupid question at all.

Depending on the cycle, duration and drugs used, nolva is recommended to improve HDL/LDL profile.

Thanks big.