Benefits In humans,<unk>  and<unk>  activity in general have been reported as having health benefits as varied as increased immunity by increasing the body's production of antibodies and subsequent lower blood pressure, and decreased risk of prostate cancer.<unk>  intimacy and orgasms increase levels of the hormone oxytocin (also known as "the love hormone"), which can help people bond and build trust. Oxytocin is believed to have a more significant impact on women than on men, which may be why women associate<unk>  attraction or<unk>  activity with romance and love more than men do. A long-term study of 3,500 people between ages 18 and 102 by clinical neuropsychologist David Weeks indicated that, based on impartial ratings of the subjects' photographs, sex on a regular basis helps people look significantly chronologically younger. Risks<unk> ly transmitted infections (STIs) are bacteria, viruses or parasites that are spread by<unk>  contact, especially vaginal, anal, or oral intercourse, or unprotected sex. Oral sex is less risky than vaginal or anal intercourse. Many times, STIs initially do not cause symptoms, increasing the risk of unknowingly passing the infection on to a sex partner or others. There are 19 million new cases of<unk> ly transmitted infections every year in the U.S., and, in 2005, the World Health Organization (WHO) estimated that 448 million people aged 15–49 were infected per year with curable STIs (such as syphilis, gonorrhea and chlamydia). Some STIs can cause a genital ulcer; even if they do not, they increase the risk of both acquiring and passing on HIV up to ten-fold. Hepatitis B can also be transmitted through<unk>  contact. Globally, there are about 257 million chronic carriers of hepatitis B. HIV is one of the world's leading infectious killers; in 2010, approximately 30 million people were estimated to have died because of it since the beginning of the epidemic. Of the 2.7 million new HIV infections estimated to occur worldwide in 2010, 1.9 million (70%) were in Africa. The World Health Organization also stated that the "estimated 1.2 million Africans who died of HIV-related illnesses in 2010 comprised 69% of the global total of 1.8 million deaths attributable to the epidemic." It is diagnosed by blood tests, and while no cure has been found, it can be controlled by management through antiretroviral drugs for the disease, and patients can enjoy healthy and productive lives. In cases where infection is suspected, early medical intervention is highly beneficial in all cases. The CDC stated "the risk of HIV transmission from an infected partner through oral sex is much less than the risk of HIV transmission from anal or vaginal sex," but that "measuring the exact risk of HIV transmission as a result of oral sex is very difficult" and that this is "because most<unk> ly active individuals practice oral sex in addition to other forms of sex, such as vaginal or anal sex, when transmission occurs, it is difficult to determine whether it occurred as a result of oral sex or other more risky<unk>  activities". They added that "several co-factors may increase the risk of HIV transmission through oral sex"; this includes ulcers, bleeding gums, genital sores, and the presence of other STIs. In 2005, the World Health Organization estimated that 123 million women become pregnant worldwide each year, and around 87 million of those pregnancies or 70.7% are unintentional. Approximately 46 million pregnancies per year reportedly end in induced abortion. Approximately 6 million U.S. women become pregnant per year. Out of known pregnancies, two-thirds result in live births and roughly 25% in abortions; the remainder end in miscarriage. However, many more women become pregnant and miscarry without even realizing it, instead mistaking the miscarriage for an unusually heavy menstruation. The U.S. teenage pregnancy rate fell by 27 percent between 1990 and 2000, from 116.3 pregnancies per 1,000 girls aged 15–19 to 84.5. This data includes live births, abortions, and fetal losses. Almost 1 million American teenage women, 10% of all women aged 15–19 and 19% of those who report having had intercourse, become pregnant each year.<unk>  activity can increase the expression of a gene transcription factor called ΔFosB (delta FosB) in the brain's reward center; consequently excessively frequent engagement in<unk>  activity on a regular (daily) basis can lead to the overexpression of ΔFosB, inducing an addiction to<unk>  activity.<unk>  addiction or hypersexuality is often considered an impulse control disorder or a behavioral addiction. It has been linked to atypical levels of dopamine, a neurotransmitter. This behavior is characterized by a fixation on<unk>  and disinhibition. It was proposed that this 'addictive behavior' be classified in DSM-5 as an impulsive–compulsive behavioral disorder. Addiction to<unk>  is thought to be genetically linked. Those having an addiction to<unk>  have a higher response to visual<unk>  cues in the brain. Those seeking treatment will typically see a physician for pharmacological management and therapy. One form of hypersexuality is Kleine–Levin syndrome. It is manifested by hypersomnia and hypersexuality and remains relatively rare.<unk>  activity can directly cause death, particularly due to coronary circulation complications, which is sometimes called coital death, coital sudden death or coital coronary. However, coital deaths are significantly rare. People, especially those who get little or no physical exercise, have a slightly increased risk of triggering a heart attack or sudden cardiac death when they engage in<unk>  or any vigorous physical exercise that is engaged in on a sporadic basis. Regular exercise reduces, but does not eliminate, the increased risk. Duration and genital complications<unk> , when involving a male participant, often ends when the male has ejaculated, and thus the partner might not have time to reach orgasm. In addition, premature ejaculation (PE) is common, and women often require a substantially longer duration of stimulation with a<unk>  partner than men do before reaching an orgasm. Scholars, such as Weiten et al., state that "many couples are locked into the idea that orgasms should be achieved only through intercourse penile-vaginal sex," that "the word foreplay suggests that any other form of<unk>  stimulation is merely preparation for the 'main event'" and that "because women reach orgasm through intercourse less consistently than men," they are likelier than men to fake an orgasm to satisfy their<unk>  partners. Painting of a couple (a prince and lady) prolonging<unk>  In 1991, scholars from the Kinsey Institute stated, "The truth is that the time between penetration and ejaculation varies not only from man to man, but from one time to the next for the same man." They added that the appropriate length for<unk>  is the length of time it takes for both partners to be mutually satisfied, emphasizing that Kinsey "found that 75 percent of men ejaculated within two minutes of penetration. But he didn't ask if the men or their partners considered two minutes mutually satisfying" and "more recent research reports slightly longer times for intercourse". A 2008 survey of Canadian and American sex therapists stated that the average time for heterosexual intercourse (coitus) was 7 minutes and that 1 to 2 minutes was too short, 3 to 7 minutes was adequate and 7 to 13 minutes desirable, while 10 to 30 minutes was too long. Anorgasmia is regular difficulty reaching orgasm after ample<unk>  stimulation, causing personal distress. This is significantly more common in women than in men, which has been attributed to the lack of sex education with regard to women's bodies, especially in sex-negative cultures, such as clitoral stimulation usually being key for women to orgasm. The physical structure of coitus favors penile stimulation over clitoral stimulation; the location of the clitoris then usually necessitates manual or oral stimulation in order for the woman to achieve orgasm. Approximately 25% of women report difficulties with orgasm, 10% of women have never had an orgasm, and 40% or 40–50% have either complained about<unk>  dissatisfaction or experienced difficulty becoming<unk> ly aroused at some point in their lives. Vaginismus is involuntary tensing of the pelvic floor musculature, making coitus, or any form of penetration of the vagina, distressing, painful and sometimes impossible for women. It is a conditioned reflex of the pubococcygeus muscle, and is sometimes referred to as the PC muscle. Vaginismus can be hard to overcome because if a woman expects to experience pain during<unk> , this can cause a muscle spasm, which results in painful<unk> . Treatment of vaginismus often includes both psychological and behavioral techniques, including the use of vaginal dilators. Additionally, the use of Botox as a medical treatment for vaginismus has been tested and administered. Painful or uncomfortable<unk>  may also be categorized as dyspareunia. Approximately 40% of males reportedly suffer from some form of erectile dysfunction (ED) or impotence, at least occasionally. Premature ejaculation has been reported to be more common than erectile dysfunction, although some estimates suggest otherwise. Due to various meanings of the disorder, estimates for the prevalence of premature ejaculation vary significantly more than for erectile dysfunction. For
Sexual intercourse
Urethral intercourse
Circumcision
Menstruation
Multiple sex partners
Hand washing
History of birth control
Bad trip