Wednesday, October 9, 2013

Birth control,

Birth control, also known as contraception and fertility control, are methods or devices used to preventpregnancy.[1] Planning, provision and use of birth control is called family planning.[2][3] Safe sex, such as the use of male or female condoms, can also help prevent sexually transmitted infections.[4][5] Birth control methods have been used since ancient times, but effective and safe methods only became available in the 20th century.[ Sony  VGP-BPS13 Battery

Some cultures deliberately limit access to birth control because they consider it to be morally or politically undesirable.[6]

The most effective methods of birth control are sterilization by means of vasectomy in males and tubal ligation in females, intrauterine devices (IUDs) and implantable contraceptives. Sony  VAIO VGP-BPS13A/B Battery This is followed by a number of hormonal contraceptives including oral pills, patches, vaginal rings, and injections. Less effective methods include barriers such as condoms, diaphragms and contraceptive sponge and fertility awareness methods. The least effective methods arespermicides and withdrawal by the male before ejaculation. Sterilization, Sony  VAIO VGP-BPS13B/B Battery while highly effective, is not usually reversible; all other methods are reversible, most immediately upon stopping them.[7] Emergency contraceptives can prevent pregnancy in the few days after unprotected sex. Some regard sexual abstinence as birth control, but abstinence-only sex education may increase teen pregnancies when offered without contraceptive education.[8][9] Sony  VAIO VGP-BPS13/S Battery

In teenagers, pregnancies are at greater risk of poor outcomes. Comprehensive sex education and access to birth control decreases the rate of unwanted pregnancies in this age group.[10][11] While all forms of birth control may be used by young people,[12] long-acting reversible birth control such as implants, IUDs, or vaginal rings are of particular benefit in reducing rates of teenage pregnancy.[11] Sony  VAIO VGP-BPS13A/S Battery

After the delivery of a child, a woman who is not exclusively breastfeeding may become pregnant again after as few as four to six weeks. Some methods of birth control can be started immediately following the birth, while others require a delay of up to six months. In those who are breast feeding progestin-only methods are preferred over combined oral contraceptives. Sony  VAIO VGP-BPS13B/S Battery

In those who have reached menopause it is recommended that birth control be continued for one year after the last period.[12]About 222 million women who want to avoid pregnancy in developing countries are not using a modern birth control method.[13][14] Birth control use in developing countries has decreased the number of maternal deaths by 40% (about 270,000 deaths prevented in 2008) and could prevent 70% if the full demand for birth control were met.[ Sony  VAIO VGP-BPS13/Q Battery

By lengthening the time between pregnancies, birth control can improve adult women's delivery outcomes and the survival of their children.[15]In the developing world women's earnings, assets, weight, and their children's schooling and health all improve with greater access to birth control.[17] Birth control increases economic growth because of fewer dependent children, more women participating in the workforce, and less consumption of scarce resources. Sony  VAIO VGP-BPS13A/Q Battery

Birth control methods include barrier methods, hormonal birth control, intrauterine devices (IUDs), sterilization, and behavioral methods. They are used before or during sex while emergency contraceptives are effective for up to a few days after sex. Sony  VAIO VGP-BPS13B/Q Battery

Effectiveness is generally expressed as the percentage of women who become pregnant using a given method during the first year[23] and sometimes as a lifetime failure rate among methods with high effectiveness, such as tubal ligation.[24]

The most effective methods are those that are long acting and do not require ongoing health care visits.[25] Sony  VGP-BPS21 Battery

Surgical sterilization, implantable hormones, and intrauterine devices all have first-year failure rates of less than 1%.[19] Hormonal contraceptive pills, patches or vaginal rings, and the lactational amenorrhea method (LAM), if used strictly, can also have first-year (or for LAM, first-6-month) failure rates of less than 1%.[25] With typical use first-year failure rates are considerably high, at 9%, due to incorrect usage.[19] Sony  VGP-BPS21A Battery

Other methods such as fertility awareness, condoms, diaphragms, and spermicides have higher first-year failure rates even with perfect usage.[25]

While all methods of birth control have some potential adverse effects, the risk is less than that ofpregnancy.[25] After stopping or removing many methods of birth control, including oral contraceptives, Sony  VGP-BPS21B Battery

IUDs, implants and injections, the rate of pregnancy during the subsequent year is the same as for those who used no birth control.[26]In those with specific health problems, certain forms of birth control may require further investigations.[27] For women who are otherwise healthy, many methods of birth control should not require a medical exam including birth control pills, injectable or implantable birth control, and condoms.[28] Sony  VGP-BPS21/S Battery

Specifically, a pelvic exam, breast exam, or blood test before starting birth control pills do not appear to affect outcomes and therefore are not required.[29][30] The World Health Organization in 2009 published a detailed list of medical eligibility criteria for each type of birth control.

Comparison of birth control methods: Different types of birth control methods have large differences in effectiveness, actions required of users, and side effects. Sony  VGP-BPS21A/b Battery

Different methods require different actions of users. Barrier methods, spermicides, or coitus interruptus must be used at every act of intercourse. The male condom may not be applied until the man achieves an erection. Barriers such as diaphragms, caps, the contraceptive sponge, and female condoms may be placed several hours before intercourse begins (note that when using the female condom the penis must be guided into place when initiating intercourse). Sony VGP-BPS26 Battery

The female condom should be removed immediately after intercourse, and before arising.[1] The other female barrier methods must be left in place for several hours after sex. Spermicides, depending on the form, may be applied several minutes to an hour before intercourse begins.

With IUDs, female or male sterilization, and hormone implant there is "little or nothing to do" post initial procedure; Sony VGP-BPL26 Battery

there is nothing to put in place before intercourse to prevent pregnancy[2] Intrauterine methods require clinic visits for installation and removal or replacement (if desired) only once every several years (5-12), depending on the device. Sterilization is a one-time, permanent procedure - after the success of surgery is verified (for vasectomy), no action is usually required of users. Sony VGP-BPS26A Battery

Implants, such as Nexplanon, provide effective birth control for three years without any user action between insertion and removal of the implant. Insertion and removal of the Implant involves a minor surgical procedure. Oral contraceptives require some action every day. Other hormonal methods require less frequent action - weekly for the patch, Sony VGP-BPS22 Battery

twice a month for vaginal ring, monthly for combined injectable contraceptive, and every twelve weeks for the injection Depo-Provera. Fertility awareness-based methods require some action every day to monitor and record fertility signs. The lactational amenorrhea method (LAM) requires breast feeding at least every four to six hours. Sony VGP-BPL22 Battery

Different methods require different levels of diligence by users. Methods with little or nothing to do or remember, or that require a clinic visit less than once per year are said to be non-user dependentforgettable or top-tier methods.[3] Intrauterine methods, implants and sterilization fall into this category.[3] Sony VGP-BPS22A Battery

For methods that are not user dependent, the actual and perfect-use failure rates are very similar.

Many hormonal methods of birth control, and LAM require a moderate level of thoughtfulness. For many hormonal methods, clinic visits must be made every three months to a year to renew the prescription. The pill must be taken every day, the patch must be reapplied weekly, or the ring must be replaced monthly. Sony VAIO PCG-3B1M Battery

Injections are required every 12 weeks. The rules for LAM must be followed every day. Both LAM and hormonal methods provide a reduced level of protection against pregnancy if they are occasionally used incorrectly (rarely going longer than 4–6 hours between breastfeeds, a late pill or injection, or forgetting to replace a patch or ring on time). The actual failure rates for LAM and hormonal methods are somewhat higher than the perfect-use failure rates. Sony VAIO PCG-3D1M Battery

Higher levels of user commitment are required for other methods.[4] Barrier methods, coitus interruptus, and spermicides must be used at every act of intercourse. Fertility awareness-based methods may require daily tracking of the menstrual cycle. The actual failure rates for these methods may be much higher than the perfect-use failure rates.

Different forms of birth control have different potential side effects. Not all, or even most, users will experience side effects from a method. Sony VAIO PCG-3G2M Battery

The less effective the method, the greater the risk of the side-effects associated with pregnancy.

Minimal or no other side effects are possible with coitus interruptus, fertility awareness-based, and LAM. Some forms of periodic abstinence encourage examination of the cervix; insertion of the fingers into the vagina to perform this examination may cause changes in the vaginal environment. Sony VAIO PCG-5R1M Battery

Following the rules for LAM may delay a woman's first post-partum menstruation beyond what would be expected from different breastfeeding practices.

Barrier methods have a risk of allergic reaction. Users sensitive to latex may use barriers made of less allergenic materials - polyurethane condoms, or silicone diaphragms, for example. Sony VAIO PCG-7162M Battery

Barrier methods are also often combined with spermicides, which have possible side effects of genital irritation, vaginal infection, and urinary tract infection.

Sterilization procedures are generally considered to have low risk of side effects, though some persons and organizations disagree.[6][7] Female sterilization is a more significant operation than vasectomy, and has greater risks; Sony VAIO PCG-7181M Battery

in industrialized nations, mortality is 4 per 100,000 tubal ligations, versus 0.1 per 100,000 vasectomies.[8]

After IUD insertion, users may experience irregular periods in the first 3–6 months with Mirena, and sometimes heavier periods and worse menstrual cramps with ParaGard. However, "ninety-nine percent of IUD users are pleased with them". Sony VAIO PCG-41112M Battery

A positive characteristic of IUDs is that fertility and the ability to become pregnant returns quickly once the IUD is removed.[2]

Because of their systemic nature, hormonal methods have the largest number of possible side effects.

Male and female condoms provide significant protection against sexually transmitted diseases (STD) when used consistently and correctly. They also provide some protection against cervical cancer.[10][11] Sony VAIO PCG-7153M Battery

Condoms are often recommended as an adjunct to more effective birth control methods (such as IUD) in situations where STD protection is also desired.[12]

Other barrier methods, such as diaphragm may provide limited protection against infections in the upper genital tract. Other methods provide little or no protection against sexually transmitted diseases. Sony VAIO PCG-71312M Battery

Some methods may be used simultaneously for higher effectiveness rates. For example, using condoms with spermicides the estimated perfect use failure rate would be comparable to the perfect use failure rate of the implant.[3] However, mathematically combining the rates to estimate the effectiveness of combined methods can be inaccurate, as the effectiveness of each method is not necessarily independent, except in the perfect case.[14] Sony VAIO PCG-7144M Battery

If a method is known or suspected to have been ineffective, such as a condom breaking, emergency contraception (ECP) may be taken up to 72 to 120 hours aftersexual intercourse. Emergency contraception should be taken shortly before or as soon after intercourse as possible, as its efficacy decreases with increasing delay. Although ECP is considered an emergency measure, Sony VAIO PCG-7191L Battery

levonorgestrel ECP taken shortly before sex may be used as a primary method for woman who have sex only a few times a year and want a hormonal method, but don’t want to take hormones all the time.[15] Failure rate of repeated or regular use of LNG ECP is similar to rate for those using a barrier method.

Hormonal contraceptives work by inhibiting ovulation and fertilization.[31] Sony VAIO PCG-3C1M Battery

They are available in a number of different forms including oral pills, implantsunder the skin, injections, patches, IUDs and a vaginal ring. They are currently available only for women. There are two types of oral birth control, thecombined oral contraceptive pill and the progestogen-only pill.[32] If taken during pregnancy, they neither increase the risk of miscarriage nor cause birth defects.[30] Sony VAIO PCG-3F1M Battery

Combined hormonal contraceptives are associated with a slightly increased risk of venous and arterial blood clots.[33] Venous clots, on average, increase from 2.8 to 9.8 per 10,000 women years[34] which is still less than that associated with pregnancy.[33] Due to this risk, they are not recommended in women over 35 years of age who continue to smoke.[35] Sony VAIO PCG-3H1M Battery

The effect on sexual desire is varied, with increase or decrease in some but with no effect in most.[36] Combined oral contraceptives reduce the risk of ovarian cancer and endometrial cancer and do not change the risk of breast cancer.[37][38] They often reduce menstrual bleeding and painful menstruation cramps.[30] The lower doses of estrogen found in the vaginal ring may reduce the risk of breast tenderness, nausea, and headache associated with higher dose estrogen products.[37] Sony VAIO PCG-3J1M Battery

Progestin-only pills, injections and intrauterine devices are not associated with an increased risk of blood clots and may be used by women with previous blood clots in their veins.[33][39] In those with a history of arterial blood clots, non-hormonal birth control or a progestin-only method other than the injectable version should be used.[33] Sony VAIO PCG-8141M Battery

Progestin-only pills may improve menstrual symptoms and can be used by breastfeeding women as they do not affect milk production. Irregular bleeding may occur with progestin-only methods, with some users reporting no periods.[40] The progestins, drospirenone and desogestrel minimize theandrogenic side effects but increase the risks of blood clots and are thus not first line.[41] Sony VAIO PCG-8161M Battery

 The perfect use first-year failure rate of the injectable progestin, Depo-Provera, is 0.2%; the typical use first failure rate is 6%.

Barrier contraceptives are devices that attempt to prevent pregnancy by physically preventing sperm from entering theuterus.[42] They include male condoms, female condoms, cervical caps, diaphragms, and contraceptive sponges withspermicide.[42] Sony VAIO PCG-3C2M Battery

Globally, condoms are the most common method of birth control.[43] Male condoms are put on a man's erect penis and physically block ejaculated sperm from entering the body of a sexual partner.[44] Modern condoms are most often made from latex, but some are made from other materials such as polyurethane, or lamb's intestine.[44] Female condoms are also available, most often made of nitrile, latex or polyurethane.[45] Sony VAIO PCG-5N2M Battery

Male condoms have the advantage of being inexpensive, easy to use, and have few adverse effects.[46] In Japan about 80% of couples who are using birth control use condoms, while in Germany this number is about 25%,[47] and in the United States it is 18%.[48]

Male condoms and the diaphragm with spermicide have typical use first-year failure rates of 18% and 12%, respectively.[19] Sony VAIO PCG-5P1M Battery

With perfect use condoms are more effective with a 2% first-year failure rate versus a 6% first-year rate with the diaphragm.[19] Condoms have the additional benefit of helping to prevent the spread of some sexually transmitted infections such as HIV/AIDS.[7]

Contraceptive sponges combine a barrier with a spermicide.[25] Sony PCG-31211T Battery

Like diaphragms, they are inserted vaginally before intercourse and must be placed over the cervixto be effective.[25] Typical failure rates during the first year depend on whether or not a woman has previously given birth, being 24% in those who have and 12% in those who have not.[19] The sponge can be inserted up to 24 hours before intercourse and must be left in place for at least six hours afterward.[25] Sony PCG-31311T Battery

Allergic reactions[49] and more severe adverse effects such as toxic shock syndrome have been reported.

The current intrauterine devices (IUDs) are usually small 'T'-shaped devices, containing either copper or levonorgestrel, inserted into the uterus.[51] They are a form of long-acting reversible birth control. First-year failure rates with the copper IUD are about 0.8% while the levonorgestrel IUD has a first-year failure rate of 0.2%.[19] Sony PCG-51111T Battery

Among the various types of birth control they, along with birth control implants, result in the greatest satisfaction among users.[52]

Evidence supports effectiveness and safety in adolescents[52] and those who have not previously had children.[53] IUDs do not affect breastfeeding and can be inserted immediately after delivery.[54] Sony PCG-81111T Battery

They may also be used immediately after an abortion.[55] Once removed, even after long term use, fertility returns to normal immediately.[56] While copper IUDs may increase menstrual bleeding and result in more painful cramps,[57] hormonal IUDs may reduce menstrual bleeding or stop menstruation altogether.[54] Other potential complications include expulsion (2–5%) and, rarely, perforation of the uterus (less than 0.7%).[Sony PCG-81311T Battery

Cramping can be treated with NSAIDs.[58]

As of 2007, IUDs are the most widely used form of reversible birth control, with more than 180 million users worldwide.[59][60] A previous model of the intrauterine device (the Dalkon shield) was associated with an increased risk of pelvic inflammatory disease; however, the risk is not affected with current models in those without sexually transmitted infections around the time of insertion. Sony VPCF138FC Battery

Surgical sterilization is available in the form of tubal ligation for women and vasectomy for men.[6] There are no significant long-term side effects, and tubal ligation decreases the risk of ovarian cancer.[6] Short term complications are twenty times less likely from a vasectomy than a tubal ligation.[6][62] After a vasectomy, there may be swelling and pain of the scrotum which usually resolves in a week or two.[63] Sony VPCF219FC Battery

With tubal ligation, complications occur in 1 to 2 percent of procedures with serious complications usually due to the anesthesia.[64] Neither method offers protection from sexually transmitted infections.[6]

This decision may cause regret in some men and women. Of women aged over 30 who have undergone tubal ligation, about 5% regret their decision, as compared with 20% of women aged under 30.[6] Sony VPCS135EC Battery

By contrast, less than 5% of men are likely to regret sterilization. Men more likely to regret sterilization are younger, have young or no children, or have an unstable marriage.[65] In a survey of biological parents, 9% stated they would not have had children if they were able to do it over again.[66]

Although sterilization is considered a permanent procedure,[67] Sony VPCS136EC Battery

it is possible to attempt a tubal reversal to reconnect the fallopian tubes or a vasectomy reversal to reconnect the vasa deferentia. In women the desire for a reversal is often associated with a change in spouse.[67] Pregnancy success rates after tubal reversal are between 31 and 88%, with complications including an increased risk of ectopic pregnancy.[67] The number of males who request reversal is between 2 and 6%.[68] Sony VPCS138EC Battery

 Rates of success in fathering another child after reversal are between 38 and 84%; with success being lower the longer the time period between the original procedure and the reversal.[68] Sperm extraction followed by in vitro fertilization may also be an option in men.

Behavioral methods involve regulating the timing or method of intercourse to prevent introduction of sperm into the female reproductive tract, either altogether or when an egg may be present.[70Sony VPCS139GC Battery

] If used perfectly the first-year failure rate maybe around 3.4%, however if used poorly first-year failure rates may approach 85%.

Fertility awareness methods involve determining the most fertile days of the menstrual cycle and avoiding unprotected intercourse.[70] Sony VPCYA15EC Battery

Techniques for determining fertility include monitoring basal body temperature, cervical secretions, or the day of the cycle.[70] They have typical first-year failure rates of 24%; perfect use first-year failure rates depend on which method is used and range from 0.4% to 5%.[19] The evidence on which these estimates are based, however, is poor as the majority of people in trials stop their use early.[70] Globally, they are used by about 3.6% of couples.[72] Sony VPCYA16EC Battery

If based on both basal body temperature and another primary sign, the method is referred to as symptothermal. Overall first-year failure rates of <2% to 20% have been reported in clinical studies of the symptothermal method.

The withdrawal method (also known as coitus interruptus) is the practice of ending sexual intercourse ("pulling out") before ejaculation.[75] Sony VPCYA25EC Battery

The main risk of the withdrawal method is that the man may not perform the maneuver correctly or in a timely manner.[75] First-year failure rates vary from 4% with perfect usage to 22% with typical usage.[19] It is not considered birth control by some medical professionals.[25]

There is little evidence regarding the sperm content of pre-ejaculatory fluid.[76] Sony VPCYA26EC Battery

While some tentative research did not find sperm,[76] one trial found sperm present in 10 out of 27 volunteers.[77] The withdrawal method is used as birth control by about 3% of couples.

Though some groups advocate total sexual abstinence, by which they mean the avoidance of all sexual activity, in the context of birth control the term usually means abstinence from vaginal intercourse.[78][79] Sony VPCYB15JC Battery

Abstinence is 100% effective in preventing pregnancy; however, not everyone who intends to be abstinent refrains from all sexual activity, and in many populations there is a significant risk of pregnancy from nonconsensual sex.[80][81]

Abstinence-only sex education does not reduce teen pregnancy.[5][82] Teen pregnancy rates are higher in students given abstinence-only education, as compared with comprehensive sex education.[82][83Sony VPCYA17GH/R Battery

] Some authorities recommend that those using abstinence as a primary method have backup method(s) available (such as condoms or emergency contraceptive pills).[84] Deliberate non-penetrative sex without vaginal sex or deliberate oral sex without vaginal sex are also sometimes considered birth control.[85] Sony VPCCW2S8E/W Battery

While this generally avoids pregnancy, pregnancy can still occur with intercrural sex and other forms of penis-near-vagina sex (genital rubbing, and the penis exiting from anal intercourse) where sperm can be deposited near the entrance to the vagina and can travel along the vagina's lubricating fluids.

The lactational amenorrhea method involves the use of a woman's natural postpartum infertility which occurs after delivery and may be extended bybreastfeeding.[88Sony VPCCW2Z1E/B Battery

] This usually requires the presence of no periods, exclusively breastfeeding the infant, and a child younger than six months.[22] The World Health Organization states that if breastfeeding is the infant's only source of nutrition, the failure rate is 2% in the six months following delivery.[89] Six uncontrolled studies of lactational amenorrhea method users found failure rates at 6 months postpartum between 0% and 7.5%.[90] Sony VPCY11S1E Battery

Failure rates increase to 4–7% at one year and 13% at two years.[91] Feeding formula, pumping instead of nursing, the use of a pacifier, and feeding solids all increase its failure rate.[92]In those who are exclusively breastfeeding, about 10% begin having periods before three months and 20% before six months.[91] In those who are not breastfeeding, fertility may return four weeks after delivery. Sony VPCY11S1E/S Battery

No comments:

Post a Comment