|
|||||||
|
|
|
|||||
|
|
|||||||
Sexual intercourse
Sexual intercourse or coitus is the human shape of copulation. In a wider context, the term sexual intercourse may pass on to a wider range of sexual activities than the term coitus, which more often than not only refers to vaginal intercourse.
Sexual intercourse may be preceded by foreplay which leads to sexual stimulation of the partners, resulting in erection of the penis and normal lubrication of the vagina. To engage in sexual intercourse, the upright penis is inserted into the vagina and one or both of the partners move back and onward to repeatedly pull the penis out (but usually not all the way out) and shove it back in. In this way, they stimulate themselves and each other usually until they attain orgasm and ejaculation. A detailed report of the physiology of sexual arousal and orgasm can be established in the article Human sexual response cycle.
Biology of conception
Coitus is the basic reproductive way of humans. During ejaculation, which normally
accompanies male orgasm, a sequence of muscular contractions delivers semen
containing male gametes recognized as sperm cells or spermatozoa into the vault
of the vagina. The following route of the sperm from the vault of the vagina
is through the cervix and into the uterus, and thence into the fallopian tubes.
Millions of sperm are there in each ejaculation, to increase the chances of
one fertilizing an egg or ovum. Sperm cells can stay alive up to nine days in
the female body. When a lush ovum from the female is present in the fallopian
tubes, the male gamete joins with the ovum resulting in fertilization and the
configuration of a new embryo. When a fertilized ovum reaches the uterus, it
becomes entrenched in the lining of the uterus known as endometrial and a pregnancy
begins.
Sexual intercourse must always be considered likely to result in pregnancy unless adequate contraceptive (birth control) actions are in force, or except one (or both) of the partners is not fertile. For example a woman who has approved through the menopause cannot conceive, but can still contribute in, and enjoy, intercourse. Where both participants are supposed to be fertile pregnancy should still be measured as a possible outcome of communication since no birth control measure is 100% effective. Coitus interrupts, or withdrawal of the penis from the vagina just previous to the man's orgasm, cannot be measured an effective method of contraception and is not recommended, as the male usually releases a small quantity of semen before the main ejaculation. If both partners are fertile, self-denial from heterosexual sexual intercourse or sterilization are the only 100% efficient ways to avoid pregnancy. Outer course, and other sexual contact (such as mutual masturbation or oral sex), in which there is sexual action without penis insertion, can be performed without resulting in pregnancy provided that semen does not come in get in touch with the vulva.
Problems of intercourse
Some males undergo from erectile dysfunction, or impotence, at least infrequently.
For those whose powerlessness is caused by medical conditions, prescription
drugs such as Viagra, Cialis, and Levitra are available. However, doctors care
against the unnecessary use of these drugs since they are accompanied by grave
risks such as increased chance of heart attack. Also, as is also often the case,
using a drug to offset the symptom, impotence, masks the fundamental problem
causing the impotence, and does not fix the problem. A serious form might be
aggravated if left untreated.
A more ordinary sexual disorder in males is premature ejaculation (PE). Those afflicted with PE can do intercourse for a standard of 1.8 minutes before experiencing an orgasm. This compares with an average of 7.3 minutes for those not pain from premature ejaculation. The U.S. Food and Drug Administration (FDA) are currently investigative the drug dapoxetine to treat early ejaculation. In clinical trials those with PE who took dapoxetine experienced interaction three to four times longer before orgasm than devoid of the drug.
The American Urological Association (AUA) estimates that early ejaculation could have an effect on 27 percent to 34 percent of men in the United States. The AUA also estimates that 10 percent to 12 percent of men in the United States are exaggerated by erectile dysfunction.
Inability to attain orgasm is called anorgasmia. It is much more ordinary in women than men and usually needs notice from both partners over a long time span to solve. Many women, particularly younger women with little sexual experience, have complexity achieving orgasm. Whether a woman considers anorgasmia a trouble or not is highly individual; the well-liked but dubious notion that both partners should achieve orgasm in "normal" intercourse may add to a woman's nervousness over anorgasmia.
Vaginismus is instinctive tensing of the pelvic floor musculature, creation coitus distressing or not possible. Dyspareunia is painful or painful intercourse; it can be due to a variety of reasons.