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Birth control

2007 Schools Wikipedia Selection. Related subjects: Health and medicine

   Birth control is a regimen of one or more actions, devices, or
   medications followed in order to deliberately prevent or reduce the
   likelihood of a woman becoming pregnant or giving birth. Methods and
   intentions typically termed birth control may be considered a pivotal
   ingredient to family planning. Mechanisms which are intended to reduce
   the likelihood of the fertilisation of an ovum by a spermatozoon may
   more specifically be referred to as contraception. Contraception
   differs from abortion in that the former prevents fertilization, while
   the latter terminates an already established pregnancy. Methods of
   birth control which may prevent the implantation of an embryo if
   fertilization occurs are medically considered to be contraception but
   characterized by some opponents as abortifacients.

   Birth control is a controversial political and ethical issue in many
   cultures and religions, and although it is generally less controversial
   than abortion specifically, it is still opposed by many. There are
   various degrees of opposition, including those who oppose all forms of
   birth control short of sexual abstinence; those who oppose forms of
   birth control they deem "unnatural", while allowing natural birth
   control; and those who support most forms of birth control that prevent
   fertilisation, but oppose any method of birth control which prevents a
   fertilized embryo from attaching to the uterus and initiating a
   pregnancy.

History

   A family planning facility in Kuala Terengganu, Malaysia.
   Enlarge
   A family planning facility in Kuala Terengganu, Malaysia.
   "And the villain still pursues her." Humorous Victorian era postcard.
   Enlarge
   "And the villain still pursues her." Humorous Victorian era postcard.

   Probably the oldest methods of contraception (aside from sexual
   abstinence) are coitus interruptus, certain barrier methods, and herbal
   methods ( emmenagogues and abortifacients).

   Coitus interruptus (withdrawal of the penis from the vagina prior to
   ejaculation) probably predates any other form of birth control. Once
   the relationship between the emission of semen into the vagina and
   pregnancy was known or suspected, some men began to use this technique.
   This is not a particularly reliable method of contraception, as few men
   have the self-control to correctly practice the method at every single
   act of intercourse. Although it is commonly believed that pre-ejaculate
   fluid can cause pregnancy, modern research has shown that pre-ejaculate
   fluid does not contain viable sperm.

   There are historic records of Egyptian women using a pessary (a vaginal
   suppository) made of various acidic substances (crocodile dung is
   alleged) and lubricated with honey or oil, which may have been somewhat
   effective at killing sperm. However, it is important to note that the
   sperm cell was not discovered until Anton van Leeuwenhoek invented the
   microscope in the late seventeenth century, so barrier methods employed
   prior to that time could not know of the details of conception. Asian
   women may have used oiled paper as a cervical cap, and Europeans may
   have used beeswax for this purpose. The condom appeared sometime in the
   seventeenth century, initially made of a length of animal intestine. It
   was not particularly popular, nor as effective as modern latex condoms,
   but was employed both as a means of contraception and in the hopes of
   avoiding syphilis, which was greatly feared and devastating prior to
   the discovery of antibiotic drugs.

   Various abortifacients have been used throughout human history,
   although many do not associate induced abortion with the term 'birth
   control'. Some of them were effective, some were not; those that were
   most effective also had major side effects. One abortifacient reported
   to have low levels of side effects— silphium—was harvested to
   extinction around the 1st century. The ingestion of certain poisons by
   the female can disrupt the reproductive system; women have drunk
   solutions containing mercury, arsenic, or other toxic substances for
   this purpose. The Greek gynaecologist Soranus in the 2nd century
   suggested that women drink water that blacksmiths had used to cool
   metal. The herbs tansy and pennyroyal are well-known in folklore as
   abortive agents, but these also "work" by poisoning the woman. Levels
   of the active chemicals in these herbs that will induce a miscarriage
   are high enough to damage the liver, kidneys, and other organs, making
   them very dangerous. However, in those times where risk of maternal
   death from postpartum complications was high, the risks and side
   effects of toxic medicines may have seemed less onerous. Some
   herbalists claim that black cohosh tea will also be effective in
   certain cases as an abortifacient.

   Presenters at a family planning conference told a tale of Arab traders
   inserting small stones into the uteruses of their camel in order to
   prevent pregnancy, a concept very similar to the modern IUD. Although
   the story has been repeated as truth, it has no basis in history and
   was meant only for entertainment purposes. The first interuterine
   devices (which occupied both the vagina and the uterus) were first
   marketed around 1900. The first modern intrauterine device (contained
   entirely in the uterus) was described in a German publication in 1909,
   although the author appears to have never marketed his product.

   The Rhythm Method (with a rather high method failure rate of 10% per
   year) was developed in the early twentieth century, as researchers
   discovered that a woman only ovulates once per menstrual cycle. Not
   until the mid-20th century, when scientists better understood the
   functioning of the menstrual cycle and the hormones that controlled it,
   were oral contraceptives and modern methods of fertility awareness
   (also called natural family planning) developed.

Methods

Physical methods

Barrier methods

   Three colored condoms
   Enlarge
   Three colored condoms

   Barrier methods place a physical impediment to the movement of sperm
   into the female reproductive tract.

   The most popular barrier method is the male condom, a latex or
   polyurethane sheath placed over the penis. The condom is also available
   in a female version, which is made of polyurethane. The female condom
   has a flexible ring at each end—one secures behind the pubic bone to
   hold the condom in place, while the other ring stays outside the
   vagina.

   Cervical barriers are devices that are contained completely within the
   vagina. The cervical cap is the smallest cervical barrier. It stays in
   place by suction to the cervix or to the vaginal walls. The Lea's
   shield is a larger cervical barrier, also held in place by suction. The
   diaphragm fits into place behind the woman's pubic bone and has a firm
   but flexible ring, which helps it press against the vaginal walls. The
   contraceptive sponge has a depression to hold it in place over the
   cervix.

Hormonal methods

   Ortho Tri-cyclen, a brand of oral contraceptive, in a dial dispenser.
   Enlarge
   Ortho Tri-cyclen, a brand of oral contraceptive, in a dial dispenser.

   There are variety of delivery methods for hormonal contraception.

   Combinations of synthetic estrogen and progestins (synthetic forms of
   progesterone) are commonly used. These include the combined oral
   contraceptive pill ("The Pill"), the Patch, and the contraceptive
   vaginal ring ("NuvaRing"). Not currently available for sale is Lunelle,
   a monthly injection.

   Other methods contain only progesterone, or a progestin. These include
   the progesterone only pill (the POP or 'minipill'), and Depo Provera (
   medroxyprogesterone acetate) given as an intramuscular injection every
   three months, and Noristerat ( norethisterone acetate), which is given
   as an intramuscular injection every 8 weeks. The progesterone-only pill
   must be taken at more precisely remembered times each day than combined
   pills. A contraceptive implant called Norplant was removed from the
   market in 2002, though a newer implant called Implanon was approved for
   sale on July 17, 2006. The various progesterone-only methods may cause
   irregular bleeding for several months.

Centchroman

   Centchroman is a Selective Estrogen Receptor Modulator, or SERM. It
   causes ovulation to occur asynchronously with the formation of the
   uterine lining, preventing implantation of a zygote. It has been widely
   available as a birth control method in India since the early 90s,
   marketed under the trade name Saheli®. It is not legally available
   anywhere outside of India, and it is not in the process of becoming
   available in the United States.

Intrauterine methods

   These are devices that are placed in the uterus. They are usually
   shaped like a "T"—the arms of the T hold the device in place inside the
   uterus. In the United States, all devices which are placed in the
   uterus to prevent pregnancy are referred to as IUDs. In the UK, a
   distinction is made between the IUDs and IUS. This is probably because
   there are seven different kinds of IUDs available in the UK, compared
   to two in the US.

   Intrauterine Devices ("IUDs") contain copper (which has a spermicidal
   effect).

   IntraUterine Systems ("IUS") release progesterone or a progestin.

Emergency contraception

   Most combined pills and POPs may be taken in high doses to prevent
   pregnancy after a birth control failure (such as a condom breaking) or
   after unprotected intercourse. Hormonal emergency contraception is also
   known as the "morning after pill," although it is licensed for use up
   to three days after intercourse.

   Copper intrauterine devices may also be used as emergency
   contraception. For this use, they must be inserted within five days of
   the birth control failure or unprotected intercourse.

Induced abortion

   Abortion can be done with surgical methods, usually suction-aspiration
   abortion (in the first trimester) or dilation and evacuation (in the
   second trimester). Chemical abortion uses drugs to end a pregnancy and
   is approved for pregnancies of less than 7 weeks gestation. Later-term
   abortions may use prostaglandins to induce premature delivery. An
   injection to stop the fetal heart may be used prior to induction.

   Some herbs are believed to cause abortion ( abortifacients). No
   peer-reviewed research has been done on these substances.

   The use of abortion as birth control is a controversial issue, subject
   to ethical debate.

Sterilization

   Surgical sterilization is available in the form of tubal ligation for
   women and vasectomy for men.

   A non-surgical sterilization procedure, Essure, is also available for
   women.

Behavioural methods

Fertility awareness methods

   Fertility awareness (FA) methods involve a woman's observation and
   charting of one or more of her body's primary fertility signs, to
   determine the fertile and infertile phases of her cycle. Unprotected
   sex is restricted to the least fertile period. During the most fertile
   period, barrier methods may be availed, or she may abstain from
   intercourse. Primary methods of determining fertility include
   monitoring of basal body temperature and of cervical mucus, while
   cervical position and other bodily cues including mittelschmerz are
   considered secondary indicators. A woman may chart these events on
   paper or with software. FA is versatile and may also be practiced to
   achieve pregnancy, by identifying the fertile period and having
   intercourse prior to and during that time.

   The term natural family planning (NFP) is sometimes used to describe
   any use of FA methods. However, this term specifically refers to a set
   of several birth control methods approved by the Roman Catholic Church.
   Research by Catholics resulted in the Billings ovulation method and the
   Creighton Model, two types of FA which are promoted as natural family
   planning. Although the physical methods used in these kinds of NFP and
   those used in FA are identical, NFP involves additional behaviour
   restrictions defined by Catholic beliefs. These restrictions are not
   specific to the practice of FA.

Statistical methods

   Statistical methods such as the Rhythm Method and Standard Days Method
   are dissimilar from observational fertility awareness methods, in that
   they do not involve the observation or recording of bodily cues of
   fertility. Instead, statistical methods estimate the likelihood of
   fertility based on the length of past menstrual cycles. The Rhythm
   Method is much less accurate than fertility awareness methods, and is
   considered by fertility awareness teachers to have been obsolete for at
   least twenty years.

Coitus interruptus

   Coitus interruptus (literally "interrupted sex"), also known as the
   withdrawal method, is the practice of ending sexual intercourse
   ("pulling out") before ejaculation. The main risk of coitus interruptus
   is that the man may not make the maneuver in time. Although concern has
   been raised about the risk of pregnancy from sperm in pre-ejaculate,
   several small studies have failed to find any viable sperm in the
   fluid.

Avoiding vaginal intercourse

   The risk of pregnancy from non-vaginal sex is low, such as outercourse
   (sex without penetration), anal sex, or oral sex. With this method,
   great discipline is required from both partners to prevent the
   progression to intercourse. Due to the level of discipline required
   while in a passionate state, this method may be considered unreliable,
   and the potential to progress to intercourse should be addressed with
   physical precautions.

Abstinence

   Sexual abstinence (also known as celibacy), is the practice of avoiding
   all sexual activity. It is highly effective if practiced consistently.
   As with avoiding intercourse, however, it may be unreliable due to the
   level of discipline required. This method cannot be considered perfect
   or infallible, because a fertile woman who practices abstinence alone
   can still become pregnant if she is raped.

Lactational

   Most breastfeeding women have a period of infertility after the birth
   of their child. The Lactational Amenorrhea Method, or LAM, gives
   guidelines for determining the length of a woman's period of
   breastfeeding infertility.

Methods in development

Experimental contraceptives for males

   Research is being done into a variety of substances that have potential
   as male oral contraceptives, or implants or injections that may be used
   as male hormonal contraceptives.

   RISUG (Reversible Inhibition of Sperm Under Guidance), is an injection
   into the vas deferens that coats the walls of the vas with a
   spermicidal substance. This method can be reversed by washing out the
   vas deferens with a second injection.

   Vas-occlusive contraception would be analogous to intrauterine
   contraception in women.

   Heat-based contraception involves heating the testicles to a high
   temperature for a short period of time.

Myths

   Modern myths and urban legends have given rise to a great deal of false
   claims:
     * The suggestion that douching immediately following intercourse
       works as a contraceptive is untrue. While it may seem like a
       sensible idea to try to wash the ejaculate out of the vagina, it
       does not work. Due to the nature of the fluids and the structure of
       the female reproductive tract–if anything, douching spreads semen
       further towards the uterus. Some slight spermicidal effect may
       occur if the douche solution is particularly acidic, but overall it
       is not scientifically observed to be a reliably effective method.
     * The suggestion to shake a bottle of Coca-Cola and insert it into
       the vagina after ejaculation is not a form of birth control, it
       does not prevent pregnancy, and doing this can also promote
       candidiasis (yeast infections).
     * It is a myth that a female cannot get pregnant the first time she
       engages in sexual intercourse.
     * While women are usually less fertile for the first few days of
       menstruation, it is a myth that a woman cannot get pregnant if she
       has sex during her period.
     * Having sex in a hot tub does not prevent pregnancy, but may
       contribute to vaginal infections.
     * Although some sex positions may encourage pregnancy, no sexual
       positions prevent pregnancy. Having sex while standing up or with a
       woman on top will not keep the sperm from entering the uterus. The
       force of ejaculation and the ability of sperm to swim overrides
       gravity.
     * Sneezing or urinating after sex are also completely ineffective,
       they do not prevent pregnancy and are not forms of birth control.
     * Toothpaste cannot be used as an effective contraceptive

Effectiveness

   Effectiveness is measured by how many women become pregnant using a
   particular birth control method in a year. Thus, if 100 women use a
   method that has a 12% failure rate, sometime during that year, 12 of
   the women will become pregnant.

   The most effective methods in typical use are those that do not depend
   upon regular user action. Surgical sterilization, Depo-Provera, and
   intrauterine devices (IUDs) all have failure rates of less than 1% per
   year for perfect use. Depo-Provera, or the shot, has a typical failure
   rate of 3%, while sterilization and IUD's still have a typical failure
   use under 1%.

   Other methods may be highly effective if used consistently and
   correctly, but can have typical use failure rates that are considerably
   lower due to incorrect or ineffective usage by the user. Hormonal
   contraceptives, fertility awareness methods, and ecological
   breastfeeding, if used strictly, have failure rates of less than 1% per
   year. Typical use failure rates of hormonal contraceptives are as high
   as 8% per year. Fertility awareness methods as a whole have typical-use
   failure rates as high as 25% per year; however, as stated above,
   perfect use of these methods reduces the failure rate to less than 1%.

   Condoms and cervical barriers such as the diaphragm have similar
   typical use failure rates (15.0% and 16%, respectively), but perfect
   usage of the condom is more effective (2% failure vs 6%) and condoms
   have the additional feature of helping to prevent the spread of
   sexually transmitted diseases such as HIV. The withdrawal method, if
   used consistently and correctly, has a failure rate of 4%. Due to the
   difficulty of consistently using withdrawal correctly, it has a typical
   use failure rate of 27% and is not recommended by some medical
   professionals, although others believe it deserves more support.

Protection against sexually transmitted infections

   Not all methods of birth control offer protection against sexually
   transmitted infections. Abstinence from all forms of sexual behaviour
   will protect against the sexual transmission of these infections. The
   male latex condom offers some protection against some of these diseases
   with correct and consistent use, as does the female condom, although
   the latter has only been approved for vaginal sex. The female condom
   may offer greater protection against sexually transmitted infections
   that pass through skin to skin contact, as the outer ring covers more
   exposed skin than the male condom, and can be used during anal sex to
   guard against sexually transmitted infections. However, the female
   condom can be difficult to use. Freqently a woman can improperly insert
   it, even if she believes she is using it correctly.

   The remaining methods of birth control do not offer significant
   protection against the sexual transmission of these diseases.

   However, so-called sexually transmitted infections may also be
   transmitted non-sexually, and therefore, abstinence from sexual
   behaviour does not guarantee 100% protection against sexually
   transmitted infections. For example, HIV may be transmitted through
   contaminated needles which may be used in tattooing, body piercing, or
   injections. Health-care workers have acquired HIV through occupational
   exposure to accidental injuries with needles.

Religious and cultural attitudes

Religious views on birth control

   Religions vary widely in their views of the ethics of birth control. In
   Christianity, the Roman Catholic Church accepts only Natural Family
   Planning, while Protestants maintain a wide range of views from
   allowing none to very lenient. Views in Judaism range from the stricter
   Orthodox sect to the more relaxed Reformed sect. In Islam,
   contraceptives are allowed if they do not threaten health or lead to
   sterilty, although their use is sometimes discouraged. Hindus may use
   both natural and artificial contraceptives.

Birth control education

   Many teenagers, most commonly in developed countries, receive some form
   of sex education in school. What information should be provided in such
   programs is hotly contested, especially in the United States and Great
   Britain. Possible topics include reproductive anatomy, human sexual
   behaviour, information on sexually transmitted diseases (STDs), social
   aspects of sexual interaction, negotiating skills intended to help
   teens follow through with a decision to remain abstinent or to use
   birth control during sex, and information on birth control methods.

   One type of sex education program, called abstinence-only education,
   promotes abstinence until marriage and does not provide information on
   birth control, or heavily emphasizes negative information such as
   failure rates. Because abstinence offers better protection against
   pregnancy and disease than sexual activity with even the best birth
   control methods, advocates of abstinence-only education believe they
   will result in decreased rates of teenage pregnancy and STD infection.
   However, some studies have found that abstinence-only sex education
   programs actually increase the rates of pregnancy and STDs in the
   teenage population.

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