After ejaculation, your partner should grasp the condom at the base of his penis as he withdraws. Remember, too, that semen can leak out of the condom into the vagina if the penis is no longer erect. They will dissolve the latex, causing the condom to break. If you need extra lubricant, choose a water soluble product such as K Y Lubricating Jelly. Pros and cons.
Condoms are relatively inexpensive and readily available.
It's best to use a diaphragm or cervical cap to hold the spermicide in place. By themselves, spermicides are effective 4 times out of 5. When used as a backup for other barrier methods, the rate is even higher. Spermicides containing nonoxynol-9 have the important added advantage of providing a degree of protection against some sexually transmitted diseases. However, use of a condom requires the cooperation of your partner, and some men dislike them.