Sexual+Intercourse

Andrew Liou =Sexual Intercourse=

Definition
Sexual intercourse is the act in which the penis is inserted into the vagina, usually followed by orgasm. In the case of sexual intercourse for the purpose of reproduction, the male body passes sperm cells into the female, fertilizing the egg.

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. Erection changes the normally soft and flaccid organ to one of greater size and rigidity to permit easier penetration into the reproductive tract of the female. Sexual intercourse both culminates and terminates in orgasm, a process in which the male expels semen—containing sperm cells, which may unite with and fertilize the female egg,—into the female’s vaginal canal ( Encyclopædia Britannica, 2011). Sexual intercourse is also known as "coitus" or "copulation", and can sometimes refer to other types of genital contact such as oral sex or anal sex.

[[image:Sexual_Intercourse.jpg width="150" height="175" align="right" caption="Sexual intercourse contributes to relational bonding and health, but carries certain risks as well."]]
Sexual intercourse among humans is often performed for the purposes of pleasure and relational bonding, rather than simply for reproduction. In addition to providing great pleasure and a sense of well - being, some research is beginning to show that sex may provide other health benefits as well. Research suggests that frequent sexual intercourse (twice a week) is associated with reduced heart attack risk, even after making the statistical adjustments necessary to account for the fact that men who have sex that often are healthier overall. Sexual activity has also been shown to slightly increase metabolism as well as provide a boost to the immune system; investigators reported that white blood cell counts went up in men after sexual activity (in this case, masturbation-induced orgasm). Researchers have also reported that women who have intercourse regularly are more likely to have regular menstrual cycles (Harvard Health Letter, 2009).

Risks
Despite having several benefits, sexual intercourse poses certain health risks as well. Perhaps the most widely known risk of sexual intercourse is sexually transmitted diseases (STD) or sexually transmitted infections (STI). According to the Centers for Disease Control and Prevention, there are over 15 million cases of sexually transmitted disease cases reported in the United States each year. There are more than 25 diseases that are known to be transmitted through sexual activity. Other than HIV, the most common STDs in the United States are chlamydia, gonorrhea, syphilis, genital herpes, human papillomavirus, hepatitis B, trichomoniasis, and bacterial vaginosis. Adolescents and young adults are the age groups at the greatest risk for acquiring an STD. Approximately 19 million new infections occur each year, almost half of them among people ages 15 to 24 (U.S. Department of Health, 2010). Failure to properly use contraceptives increases the likelihood of contracting STDs. However, proper usage of contraceptives, such as condoms, does not guarantee that STDs will not be transmitted.

In Marriage
Recent research has demonstrated that satisfaction with sexual aspects of a relationship plays a significant role in the overall relationship satisfaction of married couples - specifically, researchers have found that couples rated sexual satisfaction as one of the most important components of marital happiness and functioning (Litzinger & Gordon, 2005). Furthermore, whereas much of the research conducted thus far has addressed the contribution of sexual satisfaction to the marital relationship, other researchers have investigated the converse, exploring the contribution of relationship satisfaction to couples' sexual satisfaction. Researchers have demonstrated that among factors most highly related to sexual satisfaction, marital satisfaction is one of the most important contributors. In an interesting study conducted by Samantha Litzinger and Kristina Gordon, they found that when couples are good at communicating, sexual satisfaction fails to contribute significantly to marital satisfaction. However, when couples have difficulties communicating, then they will have greater marital satisfaction if they are sexually satisfied, than if they are not sexually satisfied. In other words, their research suggests that in couples with strong communication skills, the quality of their sex life is less essential to marital satisfaction. When couples have poor communication skills, sexual satisfaction may be able to compensate for some of the negative effects that poor communication has on relationship satisfaction (Litzinger & Gordon, 2005).

In Casual Sex
Communication for casual sex varies and is characteristically non-verbal, since the sexual partners involved are often unfamiliar with each other. The majority of communication for casual sex revolves around discovering whether or not the other party is interested in having sex, largely because the purpose of casual sex is usually physical gratification and not emotional or relational bonding. Casual partners can generally evaluate each others' willingness to engage in sexual intercourse in three ways: tacit knowing, refusal of sex, and active participation (Beres, 2010). Tacit knowing implies that two parties can somehow 'know' when they are both interested in having sex, although it may not have been expressed verbally. Tacit knowing is usually based on the behaviors and relational context of the two people involved. Refusal of sex can be expressed both verbally (saying "no"), and by using non-verbal cues (becoming tense or stiff, pulling away, hesitance). Active participation is generally a strong signal of willingness to engage in sex, and can also be expressed both verbally ("Do you have a condom?") and non-verbally (pulling closer, breathing, moaning). Despite these general rules, miscommunication does occur in casual sex as well. The two most common forms of miscommunication for casual sex include men overestimating women’s interest in sex, and women giving "token resistance" (saying "no" but meaning "yes") to sex (Beres, 2010).

Images
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