When used with spermicide, latex not only blocks sperm and STD transmission, it kills both sperm and, at least in the laboratory, some STDs. Some couples consider it a disadvantage that a condom must be put on prior to intercourse, thus interrupting foreplay. Others, however, integrate condom application as part of the foreplay. Some men find that a condom dulls sensation. Try adding just a drop of K-Y jelly to the inside of the tip to improve feeling.
Some people find condoms irritating.
Some people may be allergic to spermicides.