We need to make contraceptives available to all, free of charge, and help to eliminate cultural opposition and taboos on contraceptives. Even if you're against abortion, actually especially if you're against it, you need to be for contraceptives. They're a vital part of young peoples health and societies health in general.
Yes, I think reducing the tax on contraceptives will lower teenage pregnance because of a few simple reasons. First, with lower taxes on on the contraceptives, it means teenagers will be able to justify the purchase more due to the lower price. Secondly, they'd be more willing to spend money on it if it costs less money.