Nonoxynol-9 is a chemical that is widely used in contraceptives for its spermicidal properties.

GoldBamboo

... NONOXYNOL-9 is a type of contraceptive (birth control) that is inserted into the vagina. The creams, foams, or gels may also be applied to the outside of condoms before sexual intercourse begins. Nonoxynol-9 works by damaging and killing sperm in the vagina before they reach the uterus and fallopian tubes where fertilization usually takes place. Nonoxynol-9 used alone is less effective in preventing pregnancy than birth control pills, the IUD, or nonoxynol-9 used with another form of birth control like a condom, cervical cap, or diaphragm. Nonoxynol-9 does not provide protection from the HIV virus or other sexually transmitted disease (STD, like gonorrhea or chlamydia). ...
Drug Digest - more...

Nonoxynol-9 Systematic (IUPAC) name 2-[2-[2-[2-[2-[2-[2-[2-[2-(4- ...
Wikipedia - [full article]

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