1.)The natural way to reduce pregnancy is not to do sex.
but ot many guy/girls cant do it.
2)go for a safe sex. Condom is best thing of safe sex it help u to protect your counter part and u from dangerous diseases. if it is not a matter of concern for u, u may go for pills.pills are a bit no that safe, not only from pregnancy point but also from health point of view.
3) It is the more tough to follow but do give all pleasure what for we do sex and its without pregnancy. do all foreplay, do intercourse but let the sperm drain in ur sweetheart vagina. let sperm b drained outside.