What is contraception? Explain the barrier, surgical and chemical methods.
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 five days after sex. Effectiveness is generally expressed as the percentage of women who become pregnant using a given method during the first year,[25] and sometimes as a lifetime failure rate among methods with high effectiveness, such as tubal ligation.[26]
The most effective methods are those that are long acting and do not require ongoing health care visits.[27] Surgical sterilization, implantable hormones, and intrauterine devices all have first-year failure rates of less than 1%.[21]Hormonal contraceptive pills, patches or vaginal rings, and the lactational amenorrhea method (LAM), if adhered to strictly, can also have first-year (or for LAM, first-6-month) failure rates of less than 1%.[27] With typical use, first-year failure rates are considerably high, at 9%, due to inconsistent use.[21] Other methods such as condoms, diaphragms, and spermicides have higher first-year failure rates even with perfect usage.[27] The American Academy of Pediatrics recommends long acting reversible birth control as first line for young individuals.[28]
While all methods of birth control have some potential adverse effects, the risk is less than that of pregnancy.[27]After stopping or removing many methods of birth control, including oral contraceptives, IUDs, implants and injections, the rate of pregnancy during the subsequent year is the same as for those who used no birth control.[29]
For individuals with specific health problems, certain forms of birth control may require further investigations.[30] 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.[31] For example, a pelvic exam, breast exam, or blood test before starting birth control pills does not appear to affect outcomes.[32][33][34] In 2009, the World Health Organization (WHO) published a detailed list of medical eligibility criteria for each type of birth control.[3