Yeah, the sponge is historically a backup method, and not a primary method of BC. If you go barrier method, get a diaphram (or however the crap you spell it).
http://www.plannedparenthood.org/pp2.../birthcontrol/
Ah, planned parethood. Lists all types of BC, risks, how you use it, all that good stuff. If you don't have health insurance/ don't want your parents finding out/ don't have a lot of money you can go to planned parenthood for a consultation for cheap and on the DL.
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Sage knows our mythic history, King Arthur's and Sir Caradoc's
She answers hard acrostics, has a pretty taste for paradox
She quotes in elegiacs all the crimes of Heliogabalus
In conics she can floor peculiarities parabolous
-C'hi