acia ▁to ▁be ▁s per mic idal . ▁T tr iter p ene ▁sap on ins ▁from ▁Ac acia ▁aur icul iform is ▁were ▁found ▁to ▁have ▁s perm ▁imm obil izing ▁effect ▁in ▁vit ro . ▁This ▁ac acia ▁derivative ▁successfully ▁prevent ed ▁s perm ▁entry ▁into ▁the ▁cer v ical ▁m uc us , ▁dis rupted ▁s perm ato zo a ▁pl asma ▁memb rane ▁and ▁dis integr ated ▁the ▁ac ros om al ▁cap . ▁Today ▁it ▁is ▁understood ▁that ▁the ▁more ▁acid ic ▁the ▁v ag ina ▁is , ▁s perm ▁death ▁is ▁increased ▁due ▁to ▁a ▁host ile ▁environment . ▁ ▁A ▁mis con ception ▁about ▁s per mic ides ▁existed ▁in ▁the ▁ 1 9 8 0 s ▁and ▁ 1 9 9 0 s . ▁A ▁ 1 9 8 8 ▁literature ▁review ▁article ▁noted ▁that ▁in ▁vit ro ▁studies ▁of ▁non ox yn ol - 9 ▁and ▁other ▁s per mic ides ▁showed ▁in activ ation ▁of ▁ST D ▁path og ens , ▁including ▁H IV . ▁But ▁a ▁ 2 0 0 2 ▁system ic ▁review ▁and ▁meta - analysis ▁of ▁nine ▁random ized ▁controlled ▁tri als ▁of ▁v ag inal ▁non ox yn ol - 9 ▁for ▁H IV ▁and ▁ST I ▁prevent ion ▁involving ▁more ▁than ▁ 5 , 0 0 0 ▁women ▁( pred omin antly ▁sex ▁workers ) ▁found ▁no ▁statist ically ▁significant ▁reduction ▁in ▁risk ▁of ▁H IV ▁and ▁ST Is , ▁but ▁found ▁a ▁small ▁statist ically ▁significant