People who are sexually active should be familiar with various types of contraception available. Contraception has two main objectives:
1. prevent unwanted pregnancies;
2. prevent sexually transmitted infections (STIs).
Some people, such as those in a monogamous relationship, can be used only as a contraceptive method of birth control, while others who have multiple sexual partners may seek to avoid STIs. Since methods of contraception do not prevent all STIs and some types of contraception are more reliable than others, it is important to assess what is the best method for yourself and your partner.
Types of contraceptives
Contraceptives can be grouped into four main categories, each having their own advantages:
• methods with barrier
• hormonal methods,
• natural contraception,
Among the various types of barrier method with are: condoms, female condoms, diaphragms and cervical caps.
Condoms are made of latex, vinyl or natural products, and are unrolled onto an erect penis before sex. Condoms prevent sperm from reaching the female reproductive tract and prevent transmission of microorganisms from one person to another (for latex condoms and vinyl only). It is clear that your choice is limited if you are allergic to latex.
Female condoms cover the inside of the vagina and are put in place before intercourse. These are thin sheaths of polyurethane plastic (people allergic to latex can use them) with flexible rings at each end. One ring to insert the condom, and the other remains outside, covering external genitalia. Female condoms offer greater protection, enable women to take charge of birth control and avoid the loss of sensation many men feel when wearing male condoms. However, it is a little practice to learn how to set up properly and comfortably the female condom. The size of the female condom is larger than male condoms and are more expensive and can cost up to three to four dollars each.
Diaphragms and cervical caps do not protect against STIs, including HIV. The diaphragm is a shallow latex cup-shaped dome, while cervical caps are smaller and resemble a thimble. They are installed on the cervix, vagina, blocking the opening of the uterus. These products must always be used with a spermicide (see below). The diaphragms must be individually fitted, and cervical caps are available in 4 sizes. The physician must realize, however, in any case an annual gynecological exam to ensure that these devices are well suited. Pregnancy, weight change or abdominal surgery may require a diaphragm or another dimension.
Contraceptive sponges contain spermicide. A sponge is placed over the cervix and the spermicide kills sperm trying to penetrate. The sponge provides protection for 12 hours. Some women find it difficult to remove and some may be allergic to spermicide. Some women complain of recurrent yeast infections when they use a contraceptive sponge. When its use is combined with that of a condom (this is the recommended practice), we observed that about 1 in 50 women became pregnant during a year.
Spermicides are chemicals that kill or inactivate sperm. They are available as creams, gels, aerosols, films and soluble tablets or vaginal suppositories. Some condoms are spermicide-coated to provide increased protection.
Hormonal methods of contraception are based on the use of a progestin, most often in combination with estrogen. These female hormones regulate the reproductive cycle, including menstrual periods and ovulation.
Contraceptives as an association estrogen – progestin * are available in oral tablets. The packages are designed for you to take 1 tablet 1 time daily or monthly basis for 21 days out of 28, according to the instructions. After taking the pills for 21 days, you have your period during the fourth week. Then you will enter into a new package of pills to start a new cycle. There are also presentations called “continuous pills” designed to be taken daily for 3 months before missing a week. These periods produce 4 times per year rather than every month. The action of oral contraceptives is to:
• suppress ovulation;
• thicken cervical mucus to prevent sperm penetration;
• changing the lining of the uterus to make it more difficult implantation of fertilized ova;
• reduce the access of sperm to the fallopian tubes where the eggs are fertilized.
It is important to take the pills every day, in the prescribed order and on schedule. The risks of pregnancy increase when you do not take a tablet. Using an additional method of contraception is recommended.
Combined hormonal contraceptives are also available as patch and ring inserted into the vagina. The patch is worn on the skin weekly for 3 weeks. Menstruation occurs during the fourth week. Then the cycle begins again. The vaginal ring is worn inside the vagina for three weeks and is then removed for 1 week during which you are menstruating. Then introduced a new ring into the vagina.
Contraceptive progestin-only better suited to some women who should not take estrogen, including nursing mothers, women over 35 years, those who smoke and those who suffer from hypertension rebel. For women who have migraines with neurological changes or suffer from diabetes, sickle cell anemia or heart disease, contraceptives containing progestin only are preferable to those containing a combination of hormones.
Contraceptive progestin-only act similarly to those containing both estrogen and progestin. They can also be taken as daily pills or injections (every 3 months) or using an IUD that releases progestin. The intrauterine devices (IUDs) are shaped like a T and can be inserted into the uterus by a doctor. Progestin-releasing IUDs or copper. IUDs which release progestins act in the same manner as other contraceptives containing only progestin, and are effective for a period of up to 5 years, after which they must be replaced. These IUDs are the most effective form of reversible contraception, and they have the added benefit of reducing menstrual flow. The copper-releasing IUDs are effective for at least 10 years. Copper affects the lining of the uterus and prevents implantation. It also changes the chemical balance of the uterus and kills sperm.
The natural methods of contraception do not use any spermicides, pills, injections or other devices. One technique, called coitus interruptus, requires that the man completely removes his penis from vagina before ejaculation. This method of contraception is not the most reliable, since sperm can be released before ejaculation, and that man must demonstrate an excellent knowledge and familiarity with its reactions. About 1 in 5 couples obtained an unplanned pregnancy with the use of that method.
Rhythm methods require a woman to abstain from intercourse during her most fertile time. It may determine the time of ovulation in 4 ways, by observing: the calendar rhythm, temperature, mucus and its method Symptothermal. The calendar rhythm method is less accurate. Other methods depend on measurements of body temperature, which falls slightly before the release of eggs, and rises thereafter, and observation of the production of large amounts of watery mucus before ovulation . About 1 in 5 women using the rhythm method of contraception rhythm gets an unplanned pregnancy during the first year. The risks of pregnancy can be reduced by the addition of other methods rhythmic signs.
Sterilization is another alternative for men or women. For women, it involves tubal ligation, a procedure in which the fallopian tubes are cut and tied or blocked. The sperm’s access to the egg, preventing fertilization. For humans, vasectomy involves cutting the tubes that carry sperm from the testicles to the penis. These two methods of sterilization are considered permanent and irreversible although a very small percentage of men who undergo vasectomy reversal may become fertile again.
Side effects and complications
There is a risk of 2% to 5% the condom breaks or slips, but these risks are usually associated with inexperience in how to use them. Having the proper handling condoms reduces the risk of their tearing or slipping off, and it is important to withdraw while the penis is still erect to prevent semen from escaping. On average, 12% of couples in which the condom is the only way to get contraception unplanned pregnancy.
Women who use diaphragms may be prone to bladder infections, which may indicate a poor fit. To reduce the risk of infection, it is recommended to urinate before the establishment of the diaphragm and after intercourse. The toxic shock syndrome, which is a very rare side effect, can also occur in women using a diaphragm. When symptoms (sudden high fever, diarrhea, vomiting, sore throat, muscle and joint pain, dizziness), it should immediately remove the diaphragm and see a doctor.
Oral contraceptives are available in different concentrations. Proven side effects vary among individuals and can usually be eliminated by choosing another type of pill. It is important to consult a physician to determine the oral contraceptives that are appropriate in each case. Previously, the pill was associated with increased risks of breast and cervix. Today, the concentration of hormones has been greatly reduced. But it is important to talk with a doctor about the risks and benefits of oral contraceptives. One of their advantages is that they protect women against ovarian cancer and endometrial cancer. It is believed that oral contraceptives can be safely used by nonsmoking women until menopause. Studies suggest that women who smoke should stop using oral contraceptives at age 35, because the risk of heart disease is greater than the benefits of this method of contraception.
Estrogen found in birth combining the two hormones can cause side effects such as nausea, headache, breast tenderness, abdominal swelling and elevated blood pressure. The tablets containing only progestogens cause fewer side effects, although they may occasionally cause weight gain, acne and nervousness. As some medications reduce the effectiveness of oral contraceptives, women taking other medications or have a medical condition should consult their doctor.
The reliability of contraception varies widely used methods. The number of women who become pregnant during the first year that they use a particular method of contraception is shown below (where a range of percentages exist, the lower number corresponds to use “perfect” method while that the higher number corresponds to that of “real life”:
• condoms: 3% to 12%;
• The female condom: 5% to 21%;
• more condoms spermicide sponge: 2%;
• Diaphragm with spermicide: 6% to 18%;
• cervical caps with spermicide: 11.5% to 18%;
• estrogen oral contraceptives – progestin: 0.3% to 3%;
• tablets oral progestin-only: 0.5% to 3%;
• the patch estrogen – progestin: 0.3% to 3%;
• ring estrogen – progestin: 0.3% – 3%;
• injectable progesterone: 0.3%;
• progestin implant: less than 0.1%;
• Intrauterine devices: 0.6% to 2%;
• the rhythm method (natural contraception): 20%;
• tubal ligation: 2% (over a period of 10 years);
• coitus interruptus: 20%;
• vasectomy: less than 1%.
Emergency contraception – sometimes called “morning after pill” – is used in some cases to prevent pregnancy after unprotected sex. You can buy these tablets from the doctor or health clinics or women in some provinces, with a pharmacist. It involves taking two doses of oral contraceptives to 12 hours apart, within 3 days after unprotected intercourse. You can avoid 99% of unintended pregnancies using this method. The establishment of an IUD is another form of emergency contraception, especially when more than 3 days have elapsed since unprotected intercourse.