Nowadays, sex is so explicit, so publicized through the media, that it seems like there is nothing left to say, that everyone knows everything about the subject. This may be in appearance, on the surface of human relationships. People pretend to know everything, but teenagers are increasingly confused and do not know how to protect themselves from an unwanted pregnancy. Sexuality continues to be a mystery, especially for teenagers, who are beginning to decipher an absolutely new and consumerist world, where having more replaces being more. And in adolescence there is a search for oneself, through discoveries that include new sexual sensations. It is the search for sexual identity and the daily expression of one’s sexual role.

Adolescence is essentially marked by sexual transformations that ensure the possibility of reproduction and preservation of the species. But bodily and behavioral changes also concern new emotional and social discoveries. Even though there is a great deal of information, it is insufficient in the face of sexual fantasies and desires. Knowing is very important, but living and having sex without getting pregnant or transmitting a sexually transmitted disease is the challenge for this generation of Brazilian teenagers. Obtaining consistent and reliable information about sexuality and contraception is a new path to be followed, where there are risks and decisive crossroads, and where the health professional who deals with adolescents can play the role of a compass, allowing better guidance for preventing pregnancy(5).

Adolescents generally have a greater chance of becoming pregnant in the first six months of a relationship than adult women, due to the lack of information and access to contraceptives, and also due to the lack of planning for their sexual life, which occurs at irregular intervals. Friends or family are usually the ones who recommend the contraceptive methods to use at the beginning, until effective medical advice, gynecological examination and contraceptive guidance are sought.

How can adolescents be encouraged to use some contraceptive method? What is the best contraceptive method to recommend? Which is the most effective and has the fewest side effects? How can unplanned pregnancies be avoided and the frequency of pregnancies among adolescents in Brazil be reduced?

To prevent pregnancy, it is necessary to interrupt or prevent the ovulation process, or fertilization, or even the implantation of the egg in the endometrium. The various contraceptive techniques will act in one of these phases, and therefore have specific characteristics, some of which are not recommended or even prohibited for adolescents.

CONTRACEPTIVE METHODS

The ideal contraceptive method should be easy to apply, 100% effective, zero risk and completely free of side effects. Unfortunately, there is no method that combines all of these qualities.

In adolescence, a combination of methods is recommended in an attempt to increase the prevention of unplanned pregnancy and reduce side effects. The most commonly used combination is the condom and the combined oral hormonal contraceptive (OC).

Health professionals who work with adolescents must be knowledgeable about the various methods available and know which are most commonly used in this age group. These methods can be divided into behavioral, barrier, hormonal, intrauterine devices and surgical.

CHOOSING A METHOD

When deciding on the contraceptive method to be used, the following aspects should be taken into consideration:

1. knowledge of the specific characteristics of adolescence and the adolescent’s social and family context;

2. adequate guidance and transmission of information about the method, so that the adolescent fully understands it;

3. continuous medical and gynecological monitoring and assistance during the use of the contraceptive method.

BEHAVIORAL METHODS

Behavioral methods, such as coitus interruptus and the schedule, are widely used among adolescents, but incorrectly. None of them are indicated for this age group, as the failure rate is high. They need self-control and knowledge of their own bodies. They should be discouraged, but it is essential that they be taught the correct way to use them. The chart should be taught so that, at the very least, adolescents avoid having sex during their most fertile period. In practice, what is observed is that most unprotected sex occurs during this period, when libido is highest. The same occurs with coitus interruptus: when discouraged, they stop using any type of protection. The Billings method, based on changes in cervical mucus during the fertile period, and the symptothermal method, which requires daily measurements of basal body temperature, which fluctuates around the time of ovulation, are contraindicated for adolescents due to their level of difficulty.

OGINO-KNAUS TABLE OR METHOD

Known as the calendar method, it is based on the calculation of fertile days during the ovulation period, which occurs in the middle of the menstrual cycle, generally from the 12th or 14th day of the cycle. In general, the fertile period is around the 14th day in women who menstruate every 28 days. Unfortunately, ovulation is not precise and is influenced by several emotional and nutritional factors. Therefore, it is difficult to predict the exact time of ovulation. The average lifespan of the egg is 24 hours and that of the sperm is around 48 hours.

This method does not work in adolescence, because in general the adolescent does not remember the day she menstruated or does not count the days after menstruation correctly, making it difficult to calculate the fertile period accurately. In addition, romantic encounters are sporadic and often unexpected. Only a highly motivated, organized adolescent who is aware of her body habits and who writes down the days of her menstrual cycle in her diary will have a chance of success with the calendar. She also needs a partner who respects her decision and does not force her to have sex during her fertile period. The calendar can be used in conjunction with a condom, and although there are still risks of failure, they are smaller.

COITUS INTERRUPTI

This is not exactly a method of contraception, but a common sexual behavior among adolescents who are beginning their sexual life. It consists of removing the penis from the vagina before ejaculation begins. It is not very effective and carries a high risk! It requires a lot of self-control and discipline on the part of the man and, in addition, the secretion that precedes ejaculation may already contain sperm, hence the possibility of pregnancy. Coitus interruptus is a predisposing factor for premature ejaculation and impotence in men. In women, it impairs or prevents orgasm. It is important to remember that even if there is no complete penetration, pregnancy can occur, especially if the adolescent is in the fertile period. For these reasons, this method is not reliable in practice and should always be contraindicated in adolescence.

BARRIER METHODS

These are methods that prevent pregnancy by placing mechanical and/or chemical obstacles that prevent sperm from accessing the cervical canal. They were the first forms of contraception used, and with the emergence of AIDS they began to be valued again.

MALE CONDOM OR CONDOM

The male condom, also called a condom, consists of a latex sheath that covers the penis during sexual intercourse and retains the sperm during ejaculation, preventing its penetration into the cervical canal. As it prevents contact with the vagina, it also reduces the risk of transmitting HIV and other sexually transmitted agents.

The method is considered low cost, has no side effects and does not require medical supervision. It is easily accessible and can be purchased at pharmacies, supermarkets or other commercial establishments, and is also available at some health units. When advising on its use, it is essential to teach how to put it on and take it off. The condom should be put on before penetration, with the penis erect. The receptacle at the end of the condom should be squeezed during placement, in order to remove the air from inside it and to help unroll it to the base of the penis. The condom should be removed after ejaculation, with the penis still erect, securing it at the base to prevent leakage. The condom cannot be reused.

Despite the widespread dissemination of the method among adolescents, what occurs in practice is incorrect use, especially at younger ages. The factors that contribute to this fact are related to the disadvantages of the method, such as the need for manipulation during sexual intercourse, a high level of motivation, knowledge and skill in its use, self-confidence and interaction between the couple.

The condom is one of the only methods capable of preventing sexually transmitted diseases (STDs) and AIDS, therefore all adolescents, with or without sexual activity, should be instructed about it, since in order to achieve its constant use it is necessary to act early on in the sexual behavior of these young people, which means hard and long-term work.

FEMALE CONDOM OR FEMALE CONDOM

The female condom has the same purpose as the male condom: to form a physical barrier between the penis and the vagina. It is made of polyurethane, which is more resistant than latex, and therefore can be used with various lubricants. It is more complex to put on than the condom, requiring prior training. It consists of a thin, transparent tube with a ring at each end, one open and the other closed. The closed ring must be inserted inside the vagina and the open ring remains outside after insertion, protecting the lips of the vagina and the base of the penis during sexual intercourse. It also provides protection against STDs and AIDS.

In addition to being more expensive than the male condom, it requires more motivation and guidance, as it involves issues related to aesthetics and greater manipulation.

DIAPHRAGM

It should be used by women who are more responsible, usually in their late teens. It is a latex device that is inserted into the vagina before sexual intercourse, with spermicidal jelly, and which acts as a cap for the cervical canal, preventing sperm from entering the uterus. It is a method that has no side effects and does not interfere with the menstrual cycle. To increase its effectiveness, it should be used in conjunction with the menstrual cycle, and should only be removed eight to ten hours after sexual intercourse. A gynecological examination is required to determine the appropriate size and to teach how to insert it. After pregnancy, abortion or weight gain, another evaluation is necessary.

HORMONAL METHODS

Hormonal methods are available in various forms, combinations and therapeutic regimens. They are considered the most effective of all contraceptive methods.

COMBINED ORAL HORMONAL CONTRACEPTIVE (COP – PILL)

The contraceptive pill, one of the most studied medications in medical therapy, when used correctly is a reversible, effective and safe method, and is the most popular form of contraception known worldwide, including by adolescents. However, it is in this age group that the highest incidence of incorrect use and abandonment occurs.

OCPs contain estrogen and progesterone. The most commonly used estrogen is ethinylestradiol. The so-called low-dose pills contain amounts of less than 50µg (the most commonly used have 30 to 35µg). Currently, there are so-called ultralight pills , with doses of 15 to 20µg.

Progestogens are necessary to give greater consistency to the contraceptive power of estrogen and improve control of the menstrual cycle.

The mechanism of action consists of: inhibition of the peak of luteinizing hormone (LH) in the middle of the cycle, preventing ovulation; thickening of the mucus in the cervix, making sperm migration difficult; reduction in the glandular production of glycogen in the endometrium, making implantation difficult; changes in the contractility of the fallopian tubes.

The side effects on the organs and metabolism are related to the hormone dosage, duration of use and individual predisposing factors. Knowledge of these effects is of fundamental importance, as they constitute one of the main factors of limitation and adaptation to the method.

Most common symptoms: estrogen – headache, nausea, vomiting, dizziness, irritability and breast tenderness; progesterone – increased appetite, intermediate bleeding, hair loss, changes in libido.

In adolescents, weight gain and intermediate bleeding are factors that contribute to irregular use or abandonment of the method, and it is important to advise that these symptoms are temporary and tend to decrease with regular use.

To avoid these symptoms, one should opt for lower-dose pills with progestogens with lower androgenic, mineralocorticoid and anabolic effects.

There are several clinical situations that contraindicate the use of OCPs: liver, metabolic, neurological, thromboembolic, cardiovascular, neoplastic diseases and others that should be known to all doctors who prescribe OCPs.

The main advantages of using oral hormonal contraceptives are: high efficacy when used correctly; failure of 0.1 to 3 per 100 women/year; reversibility, with return of fertility in no more than one year after discontinuation; non-intercourse with sexual intercourse; reduction of menstrual flow and cramps, premenstrual symptoms, incidence of pelvic inflammatory disease (PID) and ectopic pregnancy, benign breast diseases, incidence of ovarian and endometrial cancer and menstrual cycle.

The ideal pill for adolescents is the one that contains the lowest doses of estrogen and progesterone, while maintaining the following characteristics: 1) it is effective as a contraceptive; 2) it allows for effective control of the cycle; 3) it causes fewer side effects; 4) it causes fewer changes in carbohydrates, lipids, and the hemostasis system.

Adolescents adapt to the method individually, and it is common for them to report symptoms not directly related to the method after the first dose, demonstrating the importance of clarification and the doctor/patient relationship.

How to use the pill is a source of doubt among adolescents. The first pack can be started on the first or second day of the cycle (the first day of the cycle is considered the first day of bleeding). The next packs will depend on the type of OC. Since forgetting to take a pill is a common problem, the time to take the OC should be related to a routine activity such as brushing your teeth. Missed doses of up to 12 hours do not have any consequences; Longer intervals (one to two days) may result in blood loss and ovulation, especially if they occur in the first seven doses, and condoms must be used as a safety method.

OCPs do not interfere with the maturation of the pituitary-ovarian axis or the fusion of bone epiphyses (only observed in hormone doses ten times higher than those used). There are no reports of deaths attributable to the pill in users under 18 years of age. The risk of neoplasia in adolescents due to the use of OCPs is practically zero.

In adolescence, unplanned pregnancies usually present a higher morbidity than the controlled use of OCPs.

EMERGENCY CONTRACEPTION OR POST-COITAL PILL

Emergency contraception (EC) refers to a method that can be used after unprotected sexual intercourse to prevent pregnancy. Its mechanism of action interferes with one or more phases of the reproductive process, depending on the phase of the menstrual cycle in which it is used, and can act on ovulation, sperm migration, egg transport and nutrition, fertilization, luteal function and implantation. It has no effect when the egg has already implanted, therefore it does not interrupt an ongoing pregnancy. The most commonly used methods are Yuzpe and those with progestogens.

The Yuzpe method has been used since 1970 and consists of 100mcg of ethinylestradiol and 500mcg of levonorgestrel in two doses administered 12 to 72 hours after intercourse. The earlier the administration, the greater the effectiveness, which is between 75% and 85% pregnancy prevention when used correctly. The main side effects are: nausea, vomiting and changes in menstrual flow.

Progestogens contain 0.75 mg of levonorgestrel. Two doses should be administered 12 hours apart up to 72 hours after intercourse. This method has a failure rate of 1.1% and is associated with a lower incidence of side effects.

Indications are: unprotected sexual intercourse, condom failure, sexual abuse, delayed menstruation when using injectable hormonal contraceptives, forgetting more than three pills and expulsion of the intrauterine device (IUD).

Emergency contraception is used for a very short period, therefore it does not have the side effects of other hormonal contraceptives.

The main contraindication is during pregnancy, although there is no evidence of teratogenic effects, and in patients with a history of thromboembolic diseases. Theoretically, emergency contraception has become another tool in the prevention of unplanned pregnancy in adolescence. The sexual behavior of adolescents, especially those of a younger age, demonstrates irregular, incorrect use or lack of use of any method, especially at the beginning of their sexual life. Theoretically, the association of emergency contraception with the methods used would be an excellent help, but we must ask ourselves whether the promotion of EC could not result in increased disregard for the use of other methods. EC should be guided, facilitated and promoted among adolescents, although always emphasizing its urgent nature, since it is not as effective as the methods used routinely and cannot serve as a substitute for them.

MONTHLY INJECTABLE

These are contraceptives that contain natural estrogen (estradiol) and synthetic progestogen in long-lasting doses for intramuscular use, thus inhibiting ovulation through action on the LH peak. They alter cervical mucus, the endometrium and tubal peristalsis.

The first injection should be given between the first and fifth day of the menstrual cycle, followed by injections every 30 days, regardless of menstruation. Its advantage over contraceptives is that it uses natural estrogens, avoiding liver inactivation, and it is also easy to apply. For adolescents, the main disadvantages are the menstrual changes observed in some users, which may end up leading to discontinuation of the method. Menstruation has great significance for adolescents: it is the certainty that they are not pregnant.

In the most recent formulations with medroxyprogesterone acetate and estradiol cypionate or norethisterone enanthate, these effects are minor, occurring only in the first months of use. Through monthly monitoring during this period, we can provide the adolescent with security, achieving good adaptation to the method.

The single application method is well accepted by adolescents and allows control by family members and the health team. In theory, this would be the ideal application method for adolescents. It has been widely recommended in this age group for immature patients with a history of repeated miscarriages, for those who do not adapt to oral contraceptives and for patients with mental problems.

QUARTERLY INJECTABLE

Trimonthly contraceptives contain only the progestogen component, depot medroxyprogesterone acetate, and do not present the contraindications attributed to synthetic estrogens. It is administered intramuscularly at a dose of 150 mg every 90 days and normally leads to amenorrhea.

There are studies that demonstrate a reduction in bone density in adolescent users of medroxyprogesterone acetate. It is not a first-choice contraceptive for this age group, and is contraindicated below the age of 16, since it does not provide great benefits in relation to other options. In specific cases, such as in the treatment of dysmenorrhea or endometriosis, its use can be analyzed.

INTRAUTERINE DEVICE (IUD)

Should only be used in adolescents who have already had children or, in some cases, who cannot use oral contraceptives due to medical problems or mental disorders, for example.

Side effects of the IUD include menstrual flow disorders, with intense bleeding and cramps, in addition to a higher risk of infectious and sexually transmitted diseases, as well as cervicitis.

If pregnancy occurs even with the IUD inserted in the uterus, it must be removed immediately due to the risk of miscarriage with complications.

SURGICAL METHODS

Tubal ligation and vasectomy are contraindicated, as they are irreversible methods. They should only be indicated in very special conditions for medical reasons and with due legal support.

ETHICAL AND LEGAL ASPECTS

Reproductive health care for adolescents, and especially regarding the prescription of contraceptives, has been the subject of several ethical and legal questions. Articles 224 and 225 of the Brazilian Penal Code define that sexual relations between minors under 14 years of age, to be considered presumed violence, depend on a complaint, and the right to guidance, privacy and prescription of contraceptives remains. The Federal Constitution and the Statute of Children and Adolescents guarantee family planning to all citizens for responsible parenthood, and it is the duty of the family and the State to guarantee children and adolescents the right to life and health. It also guarantees medical care for children and adolescents through the Unified Health System, guaranteeing universal and equal access to all health care actions. Medical confidentiality regarding consultations with adolescents and privacy, which are essential in the approach to sexuality, are guaranteed by the code of medical ethics. Family members will only be informed of the content of the consultations if the adolescents consent and in cases where the professionals conclude that family participation is essential for the adolescent’s health, and even in these cases, the adolescent will be informed.

The sexual behavior of adolescents can put them at risk, such as unwanted pregnancies, STDs and AIDS, compromising their health. The role of health professionals in preventing, providing guidance and providing assistance with contraception is clear.

CONCLUSIONS

Contraception in adolescence is a complex task that requires a joint approach: 1) guidance and assistance; 2) interconnection of sectors of society (education, health, family). Guidance should begin at increasingly early ages, with the aim of acting on the sexual behavior of adolescents.

All doctors who deal with adolescents should be made aware that their participation is essential for effective work to prevent teenage pregnancy.

Given this situation, professionals in the area involved with adolescents must be able to guide them on issues related to sexuality and contraceptive methods, as well as prescribe these methods.

It is still important to talk, ask questions, and understand one’s own sexuality and that of one’s sexual partner; invest in communicating correctly and educating to develop responsibility and respect between partners and between adolescents and health system professionals. Building a healthy relationship that involves love, affection, desire or sex also means making joint decisions and sharing responsibilities, choosing the most appropriate contraceptive method to protect oneself and one’s partner, and thus being able to calmly express new emotions and sensations, but above all, preserving life and avoiding an unplanned pregnancy.