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Consider What You and Your Partner Want and Feel Ready For: Even when we know we want to have certain kinds of sex, we may be comfortable with some things and not others. We may, for example, be comfortable having vaginal sex with a condom but not without one or be ready for vaginal sex but not anal or oral sex or vice versa. Thinking through what we feel ready for ahead of time can make it easier to communicate our boundaries to our partner s before or during sex.

Sexual intercourse , also called coitus or copulation , reproductive act in which the male reproductive organ in humans and other higher animals enters the female reproductive tract. In some vertebrates, such as fish , eggs are laid outside of the body and fertilized externally. To accomplish internal copulation, certain body and organic adaptations are necessary. In the human male, the penis serves both excretory and reproductive functions. During intercourse, the blood flow is temporarily increased and trapped in the penis so that it becomes enlarged and elevated, a condition known as erection.