PROTIVOZACHATOCHNYE SREDSTVA, METHODS

From Big Medical Encyclopedia

CONTRACEPTIVES, methods (contraceptiva) — the means and methods used for contraception.

History

Contraceptives were known in Ancient Greece, India and in the Arab countries. In Aristotle and Soran Efessky's works in «A canon of medical science» of Ibn-Sina some recommendations but to use of means of plant and animal origin for the purpose of contraception are provided. However these recommendations had empirical character since at that time there was no fair idea of process of fertilization yet. Only after men's and female sex cells were open, scientific development of questions of contraception (contraception) began. Due to the increase in frequency of abortion highly effective P.' search by the village is very urgent.

Items of page are subdivided into two groups: applied by the woman and applied by the man. By the nature of action they are classified on mechanical contraceptives (vulval diaphragms, cervical caps, a male condom); chemical contraceptives (creams, pastes, tablets, balls, candles, powders, solutions, aerosols entered into a vagina); a physiological method of contraception (by periodic abstention); operational methods (sterilization of men and women); the combined methods (e.g., mechanical with chemical, etc.). Modern methods of contraception are intrauterine contraceptives (intrauterine contraception) and hormonal contraceptives.

Mechanical contraceptives

the Mechanism of their action is based on creation of a mechanical obstacle to merge of a spermatozoon to an ovum. The most widespread means is the male condom (see). The essential advantage of condom consists that he not only prevents approach of pregnancy, but also protects from venereal diseases; a shortcoming — obtusion of sexual feeling. Before implementation of modern methods of contraception (intrauterine and oral contraceptives) use of condom was the most widespread method of contraception.

Fig. 1. Cervical caps (and — in) and a vulval diaphragm ().

Women use vulval diaphragms and cervical caps (fig. 1) for contraception. Vulval diaphragms are selected by the doctor; the woman before the sexual intercourse enters them and deletes not later than in 8 — 10 hours after it. Cervical caps are selected and put on a neck of uterus by the doctor not earlier than in 2 — 3 days after the termination of periods; it is possible to leave them on a neck of uterus no more than 7 days. Contraindications to use of vulval diaphragms and cervical caps: inflammatory processes of generative organs, especially necks of uterus, suspicion on pregnancy, the period within 3 — 4 months after the delivery and 1 — 2 month after abortion. Use of vulval diaphragms and cervical caps in combination with chemical contraceptives is more effective.

Chemical contraceptives

the Mechanism of action of chemical contraceptives is based on their spermotoxic effect. They are issued in the form of creams, pastes, tablets, balls, candles, powders, solutions, aerosols. Gramitsidinovy paste (see. Gramitsidin ), released in tubas with the special plastic syringe tip, enter before the sexual intercourse into a vagina (5 — 6 g of paste). Contraceptinum of T — vulval suppositories, contain boric acid (0,3 g), tannin (0,06 g), Chinosolum (0,03 g) and a fatty or lanolin basis (to weighing suppository no more than 1,9 g); enter into a vagina in 5 — 6 minutes prior to the sexual intercourse. Galascorbinum (tablets on 0,5 and 1 g) which part complex compound of potassium salts of ascorbic and gallic acids is, is entered into a vagina in 5 — 10 minutes prior to the sexual intercourse. Lutes urin (tablets and balls), contain vegetable matter (alkaloid from rhizomes of a yellow jug); they are entered in 5 — 10 minutes prior to the sexual intercourse. Apply also vulval balls which as spermotoxic components include Chinosolum (0,03 g), quinine a hydrochloride (0,3 g), boric acid (0,1 — 0,3 g), lactic acid (0,15 g) on a gelatinous or fatty basis; they are entered into a vagina in 5 — 10 minutes prior to the sexual intercourse.

Chemical contraceptives are not recommended to be applied at the increased general and local sensitivity of an organism of the woman to medicines, existence of old ruptures of a crotch after the delivery and omission of walls of a vagina.

Intrauterine contraception

Attempts of use of intrauterine contraceptives (intrauterine contraceptives) belong to the end 19 — the beginning is 20 century old, however during Hippocrates's era there were viutrimatochny devices for contraception. The beginning of scientific development of intrauterine P. of page is connected with Grefenberg's work (1929); the intrauterine contraceptives made of silk threads and a silver wire and then spiral rings from a silver or gold wire were offered them. In the 60th the pilot and clinical researches which showed efficiency of this method and allowed to prove its broad use began to be conducted.

Fig. 2. Various forms of intrauterine contraceptives (intrauterine contraceptives): in an upper number of the second at the left — a contraceptive «loop», in the lower row the first on the right — a contraceptive of the T-shaped form.

For production of intrauterine contraceptives polyethylene, in a smaller measure — nylon is preferential used. Intrauterine contraceptives are very variable in a form (fig. 2). The most widespread look is «loop» (intrauterine contraceptives of firstgeneration). However in the next years even more often began to apply viutrimatochny contraceptives of the T-shaped form or in the form of figure «7» which vertical axis is wrapped by a copper wire. Also intrauterine contraceptives containing gestagena are offered (progesterone, levonorgestrol, Norethisteronum). Such improved copper - and gormonosoderzhashchy viutrimatochny contraceptives are considered as viutrimatochny contraceptives of the second and third generation.

In our country polyethylene «loops» are issued. Distinguish several sizes viutrimatochny contraceptives. The loops size is defined by width of its greatest part (No. 1 — 25 mm, No. 2 — 27,5 mm, No. 3 — 30 mm). Intrauterine contraceptives shall meet the following requirements: ease of introduction, low interest of spontaneous exiles (ekspulsiya), availability of detection in a uterus, the minimum possibility of complications, ease of removal (if necessary).

The mechanism of action of intrauterine contraceptives is caused by a number of factors: stimulation peristalnik of uterine tubes and, as a result of they are the accelerated hit of an oospore in a cavity of the uterus; disturbance of implantation of fetal egg in a decidua of a uterus, hl. obr. owing to changes of chemical properties of the environment; mechanical obstacle of a pas of a way of penetration of spermatozoa into a uterus and uterine tubes; mobilization in an endometria of neutrophils and macrophages whose subject to action are an oospore and spermatozoa which got into a uterus. The mechanism of action of cupriferous intrauterine contraceptives is connected with local contraceptive impact of copper ions on an endometria (significant increase in activity of acid phosphatase in a proliferative phase and decrease of the activity of an alkaline phosphatase in a secretory phase of a menstrual cycle). The contraceptive effect of the intrauterine contraceptives containing gestagena is caused by change of properties of an epithelium of uterine tubes and nek-ry other factors.

Contraindications to use of intrauterine contraceptives are acute (or subacute) inflammatory diseases, high-quality and malignant new growths of female generative organs, malformations of a uterus, istmiko-cervical insufficiency, disturbances of a menstrual cycle. Use of intrauterine contraceptives for the women who underwent uterus operations (Cesarean section, a myomectomy) is dangerous, it is recommended to use other methods of contraception.

Fig. 3. Intrauterine contraceptive and syringe conductor.
Fig. 4. Diagrammatic representation of stages of introduction of an intrauterine contraceptive: and — introduction of a contraceptive in the syringe-pro-water-transport worker; - introduction of a contraceptive with the help the syringe conductor to the canal of a neck of uterus; in — introduction of a contraceptive to a cavity of the uterus; - the provision of a contraceptive in a cavity of the uterus (the syringe conductor is removed).

Introduction of intrauterine contraceptives to a cavity of the uterus is carried out after the careful gynecologic research and uterine probing for the solution of a question of selection of type and the size of a contraceptive. Special polyethylene syringes-pro-water-transport workers (fig. 3) are applied to introduction of intrauterine means. Previously intrauterine contraceptive and the syringe conductor will sterilize, placing them in disinfecting solution. It is more reasonable to use sterile intrauterine contraceptives and syringes conductors in individual packaging. Before introduction of an intrauterine contraceptive the vagina and a neck of uterus are processed disinfecting solution and if it is required, broaden the cervical channel (at not giving birth women). For direct vision the majority of intrauterine contraceptives has polyethylene thread on the end, to-ruyu later introduction it in a uterus is cut off at distance apprx. 2 cm below an outside uterine pharynx. In fig. 4 stages of introduction of an intrauterine contraceptive to a cavity of the uterus are shown. Optimum time for introduction of an intrauterine contraceptive — at once upon termination of periods (on 4 — the 7th day of a cycle); to the women who transferred artificial abortion — after the termination of the next periods; after the delivery — not earlier, than in 3 months. Perhaps also introduction of an intrauterine contraceptive right after the artificial abortion made in the first trimester of pregnancy.

Cupriferous intrauterine contraceptives are most effective. The number of cases of approach of pregnancy to 100 women applying them in the first year of observation does not exceed 1.5%; for other intrauterine contraceptives this percent hesitates from 3 to 5.

At many women within several months after introduction of intrauterine contraceptives lengthening of a menstrual cycle and increase in blood loss is noted a nek-swarm during periods; further menstrual function is usually normalized. Sometimes bloody allocations are observed in the intermenstrual period owing to traumatic impact of an intrauterine contraceptive on a mucous membrane of a uterus. Frequency of acute inflammatory diseases of female generative organs (an endometritis, an adnexitis, etc.) as a result of carrying an intrauterine contraceptive makes up to 5%. Frequency of endometrial cancer does not increase. 10 — 20% of women after introduction of an intrauterine contraceptive can have colicy pains in the bottom of a stomach which proceed from several hours to several days. The most terrible complication at use of an intrauterine contraceptive (it is preferential at the time of its introduction) — perforation uterus (see), edges it is observed in one case on several thousands of introductions. Very seldom intrauterine contraceptives can spontaneously perforate a wall of a uterus and get into an abdominal cavity. The accounting of contraindications, observance of rules of introduction of intrauterine contraceptives and dynamic overseeing by women is necessary for the prevention of by-effects and complications. For the purpose of definition of the location of an intrauterine contraceptive the research is applied ultrasonic or rentgenol; that the last was feasible, polyethylene intrauterine contraceptives impregnate barium or enter into them fine metallic thread. An adverse effect of intrauterine contraceptives on the subsequent genital function of the woman it is not established, at 90% of women conception happens usually within the first year after its extraction.

Earlier at approach of pregnancy at the women carrying intrauterine contraceptives its further development in the presence of a contraceptive in a uterus was allowed (out of an amniotic cavity). Due to the revealed increased frequency of acute inflammatory diseases of generative organs at women with their intrauterine contraceptives as soon as pregnancy is diagnosed, it is recommended to delete.

Duration of use of intrauterine contraceptives shall not exceed

2 — 3 years then they are taken and in the absence of contraindications in 2 — 3 months enter new. In process of improvement of intrauterine contraceptives duration of their use increases.

Indications for earlier removal of an intrauterine contraceptive are the menorrhagias which are not giving in to conservative therapy and a metrorrhagia, development of acute inflammatory process, megalgias in the field of pelvic bodies.

Fig. 5. Diagrammatic representation of removal thread of an intrauterine contraceptive.

Delete an intrauterine contraceptive by a pandiculation for the thread which is in a vagina (fig. 5). In case of a separation of thread, expansion of the channel of a neck of uterus and tool removal of a contraceptive is made.

Hormonal contraception

For hormonal contraception most often use the drugs (small doses of estrogen and gestagen) combined estrogen-gestagennye. From estrogen are most often used ethinylestradiol or mestranol, from gestagen — a noretynodrel or Norethisteronum (see. Norsteroida ). They are issued preferential in the form of tablets for intake and therefore are called oral contraceptives; are created by J. Rock and G. Ping-kusom. Since 1960 mass use of oral contraceptives is begun. In our country most were widely adopted Bisecurinum, non-ovlon, etc.

The contraceptive effect of oral contraceptives is connected with their action on gipotalamo-pituitary system, ovaries, uterine tubes, an endometria. There is a braking (suppression) of process of an ovulation owing to oppression of cyclic secretion of luteinizing hormone at the hypothalamic level. At the women applying oral contraceptives in the middle of a menstrual cycle the preovulatory peak of excretion of estrogen, and in the second phase of a cycle — increases in secretion of progesterone, basal (rectal) temperature monophase is not observed. In an endometria after bystry regression of a proliferative phase development of secretory changes is noted earlier. At prolonged use of oral contraceptives the endometria becomes thin and hypoplastic, after drug withdrawal normalization of its structure comes to the end within several months. Oral contraceptives exert impact on processes of migration of an ovum in uterine tubes, implantation of an oospore. 2 — 10% of women, despite reception of oral contraceptives, have an ovulation, however pregnancy does not occur. The contraceptive effect in similar cases is explained by change physical. - chemical properties of slime of the channel of a neck of uterus, decrease in a physical activity of uterine tubes.

Use of oral contraceptives is contraindicated at thrombophlebitises and tendency to thrombosis, a varicosity, diseases of a liver, benign and malignant tumors of generative organs and mammary glands, an idiopathic hypertensia, a serious cardiovascular illness, migraine, obesity, a diabetes mellitus, rheumatism, diseases of kidneys, a chorea, an allergy, a condition of a depression, bronchial asthma, disturbances of a hemogenesis, an otosclerosis. It is not necessary to apply oral contraceptives in the period of a lactation.

Usually they begin to be accepted for the 5th day of a menstrual cycle on 1 tablet a day within 21 days (one packaging contains 21 tablets). Upon termination of administration of drug in 1 — 3 day, as a rule, there comes menstrualnopodobny reaction, edges 4 — 5 days on average proceed. Sometimes after reception of 21 tablets menstrualnopodobny reaction is not observed. In these cases in 7 days after the end of reception of tablets of the first packaging it is necessary to begin to take a pill of the following packaging.

Efficiency of oral contraceptives at the correct use high (reaches 98%). The risk of conception increases at non-systematic reception of tablets.

At use of oral contraceptives there can be by-effects and complications: increase in body weight, painful feelings in mammary glands, a headache (in intervals between administrations of drug), a depression, a hypertrophic ulitis, vulval allocations (bleach), nausea (especially at the beginning of use of drug), uterine bleedings or bloody allocations (it is preferential during the intermenstrual period), decrease in libido. Carry to the heaviest complications fibrinferments and thromboembolisms. They are caused by the changes occurring in system of a hemostasis at long use of oral contraceptives (decrease in a blood clotting time with not changed duration of bleeding, reduction of a prothrombin time, increase in concentration of fibrinogen, fibrinolitic activity of blood, the maintenance of factors of blood VII and VIII). These changes are connected generally with effect of the estrogen which is contained in drug.

The factors increasing risk of development of by-effects and complications during the use of oral contraceptives are smoking, alcoholism and obesity. The possibility of development of cancer of uterus or mammary glands as a result of long reception of oral contraceptives cannot be considered proved.

(Or preventions) complications and by-effects it is necessary for decrease in frequency: to strictly consider contraindications at purpose of oral contraceptives; at a possibility of the choice to recommend drug with the smallest content of estrogen and gestagen; before use of drugs to collect the detailed anamnesis and to carry out bulk analysis of blood and urine, a research of system of a hemostasis, tsitol. structure of contents of a vagina for identification of atypical cells, function of a liver (in the presence in the anamnesis of instructions on the postponed diseases of a liver); to carry out dynamic overseeing by the women accepting oral contraceptives, at least 2 times a year (carry out determination of body weight, gynecologic inspection, survey and a palpation of mammary glands, a research of system of a hemostasis, according to indications — functions of a liver). At resistant by-effects it is necessary either to replace drug, or to recommend to the woman other method of contraception.

For contraception also the drugs containing only microdoses of a gestagen (Norgestrelum, etc.) without oestrogenic component are offered. Such drugs (femulen, kontinuin, etc.) received the name «minipills». These oral contraceptives are safer, than the drugs combined estrogen-gestagennye, however are less effective.

After the termination of reception of oral contraceptives genital function at women, as a rule, is not broken; at 80 — 90% approach of pregnancy in the first 6 months is noted.

Duration of use of oral contraceptives shall not exceed 1 — 1,5 years. After a break lasting 3 — 4 months, in time to-rogo there is a recovery of oppressed function of system of regulation of a menstrual cycle, oral contraceptives can be reappointed. In this time term the woman should recommend to use other method of contraception since at 60 — 70% pregnancy occurs in these terms.

Oral contraceptives which can be applied once a month are developed; however at their use menstrualnopodobny bleeding is irregular; the indicator of inefficiency is high.

The injection prolonged drugs lasting action of 3 months are offered (the DUMP — depoobrazuyushchy acetate of a medroksiprogesteron; NET — ЭН Norethisteronum enanthate). The mechanism of their action is caused by suppression of secretion of gonadotrophins (especially cyclic emission of luteinizing hormone), anovulation, increase in viscosity of slime of the channel of a neck of uterus, change of secretory transformation of an endometria. Efficiency of drugs high. However at their reception menstrualnopodobny bleedings are irregular, the amenorrhea, increase in body weight is observed.

For the purpose of braking of implantation of an oospore use of high doses of estrogen after the sexual intercourse is recommended; however possible serious complications (bleedings and thromboembolisms) limit use of this type of hormonal contraception.

Carry out works on research of an oral contraceptive for men (contraceptive tablets) which would interfere with formation of spermatozoa or oppressed them maturing and (or) ability to impregnate an ovum. In our country the injection prolonged drugs, high doses of estrogen, and also oral contraceptives are not applied to men.

Other methods of contraception

Krom of the given methods, contraception can be reached by a physiological method, or method of «rhythm». It is based on abstention from the sexual intercourses when usually there comes conception (in each menstrual cycle). For conception the days of a menstrual cycle close to an ovulation are considered as optimum days. At the same time consider terms of the ovulation which is usually coming on 12 — the 16th day at a 28-day cycle, life expectancy of a mature ovum (till 24 o'clock), and also fertilizing capacity of spermatozoa (to 48 hours after the sexual intercourse). The method is offered in the 20th of our century by K. Ogino and H. Knaus; the women given a monthly menstrual calendar were taken as a basis. Further it was established that efficiency of a method significantly increases at measurement within 3 months in a row of basal (rectal) body temperature that allows to establish the term of an ovulation.

For simplification of use of a method special tables are offered, however it is necessary to remember that the ovulation can come sooner or later the erik specified in them.

Sometimes use special formulas. At a regular menstrual cycle in a cycle subtract from total number of days 18, receive the first day of the «dangerous» period; then in a cycle subtract from total number of days 11 and receive the last day of the «dangerous» period. So, this («dangerous») period at a 28-day menstrual cycle proceeds from the 10th (28 — 18) to the 17th (28 — 11) days of a cycle inclusive. This method is unacceptable at irregular or very short cycle. At the correct use and a regular cycle efficiency of a method of «rhythm» approaches 90%.

Operational methods of contraception in the form of sterilization of men (partial excision or bandaging of a deferent duct) and women (a section, partial excision or bandaging of uterine tubes) are admissible only on special medical indications (see. Sterilization sexual ).

Also advanced methods of surgical sterilization are developed (diathermocoagulation of uterine tubes and imposing of brackets under control of a laparoskop; a gisteroskopichesky method of occlusion of pipes at direct vision).

The interrupted sexual intercourse, used as a warning facility of pregnancy, it is not physiologic, unhealthy men and women and is accompanied by great emotional pressure (see. Sexual intercourse ). However the opinion on possible development of adverse effects of this method as at women (developments of stagnation in a small basin, frigidity, development of dysfunction of ovaries), and at men (a neurasthenia, impotence, a prostatauxe) admits not all researchers.


Bibliography: Manuylova I. A. and Antipova N. B. Influence of intrauterine funds with copper for reproductive system of the woman, Akush. and ginek., No. 10, page 49, 1978, bibliogr.; New methods of regulation of fertility, the Report of science team of WHO, the lane with English, M., 1975; P e t r about in - M and with l and to about in M. A., etc. Modern contraceptives, L., 1973, bibliogr.; Sleptsova S. I. Modern methods of regulation of fertility, Akush. and ginek., To 10, page 5, 1980, bibliogr.; The reference book on obstetrics and gynecology, under the editorship of JI. S. Persianinova and I. V. Ilyin, page 210, L., 1980; The development of and new triphasic oral contraceptive, ed. by R. B. Greenblatt, Lancaster, 1980; Roland M. Response to contraception, Philadelphia and. o., 1973; Taubert H. D. u. Kuhl H. Kontrazeption mit Hormonen, Stuttgart — N. Y., 1981.

B. L. Gurtova.

Яндекс.Метрика