The risk is minimal. The background is that the World Health Organization did a study a few years ago to determine if Nonoxynol-9 helped prevent HIV transmission. In the process they determined it could actually increase the chance of transmission. Here's why: Nonoxynol-9, the world's most common spermicide, is a detergent and it can have weakening effect on the skin allowing HIV to enter the body through microscopic breaks.
Governments and companies have over-reacted with warning such as you cite. The vagina is forty cells thick. This allows high elasticity and it also guards against these tears. The anus is one cell thick and tiny tears are common with anal sex. Males is same sex relationships do not need spermicide; do not use condoms with Non-9. I also recommend that heterosexual couples doing anal, they not use Non-9.
For vaginal sex, there is little problem. Non-9 has been used for over fifty years with, perhaps, 2% of all women having any reaction. For women who have some reaction, determine whether it is to latex or to Non-9. If it is to Non-9 look for products containing Benzalkonium or Octoxynol-9. Some spermicidal products use a combination.
The benefits of using a spermicide in the vagina are much greater than the risks. I have spent entire weekends pumping that stuff into me and so have millions of other women. Prostitutes often use a tube a week of vaginal jelly.
The risks, in normal sex, are very, very low.
Brandye
Posted: 28 Sep 00:46