How hormonal contraceptives work in the animal's body. What contraceptives should I give my cat? The principle of action of hormonal contraception
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The reproductive instinct worries the cat several times a year. The animal becomes obsessively affectionate, meows in an unusual voice, howls, and may mark the owner’s things. There are only 3 options to stop or prevent such unwanted behavior:
- planned pregnancy;
- sterilization with removal of the uterus and ovaries;
- giving contraceptives for cats in tablets or injections.
It is very difficult to distribute offspring from a mongrel cat; abdominal surgery is scary. The most convenient option for the owner is contraception for cats. “What drugs are used and in what case, is it safe?” - these are the questions cat owners ask veterinarians.
There are two types of drugs on the market to prevent females from estrous: injectable and in drops or tablets for oral use. The methods discussed will allow the owner to decide which contraceptives for cats are best to use in his case. For each method, the risks of side effects and the cost in relation to routine sterilization are indicated.
Birth control pills and drops for cats
This is the simplest and most inexpensive type of contraception for cats. Birth control pills and drops can be purchased at any veterinary pharmacy and even at a pet store. The most frequently presented are “ContraSex”, “Kontrik”, “Gestrenol”, “Sex Barrier”, “Nonoeston”, “Pillkan”, “EX-5” and others. The products are available in the form of tablets and drops.
The liquid fraction will be convenient for dosing with food. It can be used in all animals. The preparations contain two active ingredients.
Acetobumedone
Acetobumedone or analogues, mepregenol acetate, acts on areas in the pituitary gland and hypothalamus, blocking the synthesis of substances necessary for estrus - follicle-stimulating and luteinizing hormones. In this regard, the drugs are similar to injectable contraceptives for cats and even to drugs used for contraception in women.
Ethinyl estradiol
The second active ingredient, ethinyl estradiol or its analogues, enhances the contraceptive effect by changing the internal environment of the uterus. On the one hand, this is necessary, because different rates of absorption of a single dose of the drug from the gastrointestinal tract cannot guarantee protection against pregnancy and the complete absence of estrus. If its manifestations are weak, fertilization is not excluded. This action of the drug inside the uterus is risky for the cat's health. Changes in the structure of the endometrium most likely lead to persistent and long-term pathology. The drugs have not received positive evaluations in studies and are not available for free sale in a number of countries.
Complications from self-medication
Unfortunately, widespread availability coupled with inappropriate administration regimens has caused serious hormonal tumors in animals.
Increase in the size of the mammary glands
This is one of the not the most terrible, but common pathologies. Veterinarians have come across cases where the glands have enlarged to the size of an average lemon in a few months. In this case, only surgery is indicated to remove both rows of glands, the uterus and the ovaries. The intervention is complicated by the fact that the skin stretched by the protruding mammary glands has to be excised; as a result, the skin on the abdomen after the operation will be in a tense state, which greatly worries the animal. The rehabilitation period depends on the size of the removed glands and lasts up to a month. Of course, the owner will have to tinker a lot more with restoring the pet.
Endometritis
This is the second risk from using contraceptive drops and pills. The lining of the uterus changes structure, causing it to become rigid and twisted. The animal may not show a clinical picture of the disease for a long time, and the inflammatory process will degenerate into a tumor over time. When discharge becomes noticeable, the cat loses weight, and the tumor is palpable, the veterinary surgeon often cannot do anything - the patient is inoperable.
Pyometra
The third highest risk of birth control complications for cats. In a closed form, pus accumulates in the uterus, which does not come out through the vagina. In the open form, leakage is observed, which decreases during the course of antibiotics. When the uterus ruptures, the animal dies from peritonitis. Treatment for pyometra in cats is only surgical. During the operation, there is a risk of pus entering the abdominal cavity, which provokes peritonitis. Even with a normally performed operation, the doctor cannot guarantee success: the inflamed inner layer of the uterus tends to form adhesions with nearby organs.
Ovarian cysts or tumors are present in 50-70% of cats operated on after courses of contraceptives. They can reach the size of a quail egg, are easily palpable and often, in the absence of ultrasound examination, can be mistaken for enlarged kidneys.
According to average clinic statistics, up to 95% of patients who sought surgical help due to uterine pathology were given birth control pills one or more times.
Contraceptive injections for cats
An analogue of inexpensive birth control pills for cats are long-acting injectable drugs. The difference from tablets and drops is that the contraceptive effect is independent of the gastrointestinal tract: the substance enters directly into the animal’s bloodstream. This made it possible to exclude a hormone that affects the endometrium.
"Cowinan"
A veterinary injectable drug with contraceptive action is Covinan. It is created on the basis of prolygestone - a synthetic analogue of the “pregnancy hormone” progesterone. The active substance suppresses the production of hormones characteristic of female estrus, as a result of which the animal does not come into heat.
"Depot Promon"
The American drug Depo Promon, containing medroxyprogesterone acetate as an active ingredient, is popular. The compound is used in gynecology, so the specific effects on the body and side effects have been studied in different animals. The drug is recommended as a temporary contraceptive for cats used for breeding that need to go through several heats. The active ingredient of the drug affects the pituitary gland, reducing the ability to secrete the hormone gonadotropin, preventing follicle maturation and the onset of ovulation. This makes pregnancy impossible during the duration of the medication.
The advantage is the thinning of the endometrium, due to which the cat’s risk of developing endometritis and pyometra is reduced during the period of use of contraceptives. "Depo Promon" is used subcutaneously at intervals of 6 months. Its effect decreases gradually, so normal pregnancy can occur after 6-9 months from the date of the last injection. The drug has contraindications - they are indicated in the instructions. It should not be given for the first time to cats older than 5-6 years.
The medical product Depo Provera, which contains 3 times more of the same active substance, has a similar effect. This is also due to the antitumor effect.
"Depo Provera"
The downside of the drug is the cost. A one-year course of using a contraceptive injection for cats is comparable in cost to removing the uterus and ovaries. The drugs are justified for use (this is why they were developed) in nurseries, where periods of rest from pregnancy and lactation are provided for females. Modern studies have confirmed the risks of side effects from using contraceptives for cats in injections, but they are much lower than when using oral contraceptives.
Complications from a course of medications lie on the conscience of the owners. There are often cases when the owner of a cat that has already gone on a spree comes to the clinic for an injection. In this situation, the doctor, without asking or receiving information about the regularity and duration of the sexual cycle and the date of the last estrus, gives a contraceptive injection almost “blindly”.
Veterinarians have differing opinions about the safety of using contraceptives. The best picture is seen by surgeons who often perform abdominal operations to remove the uterus and ovaries. They see firsthand the consequences of sometimes a single use of inexpensive tablets: changes in the size and structure of the ovaries, endometritis and pyometra. If the animal is used for breeding, the owner evaluates the risks and benefits of giving contraceptives to the cat in tablets or injections. If you do not plan to produce offspring on a regular basis, then it is recommended to sterilize the cat.
Fertilization in a woman's body is a complex biological process. Medical progress allows women today to avoid unwanted fertilization and subsequent fetal development with the help of contraceptives. In this article we will try to explain the principle of action of female contraceptives.
Main the essence of the action of birth control pills- intervene in the female cycle and change it with the help of artificial hormones and synthetic estrogens and progesterones. These compounds vary depending on a particular product and differ from natural hormones.
Combined method
This method involves the use of synthesized estrogen and progesterone throughout the entire cycle (21 days).
Various combinations are used:
Monophasic drugs
All tablets in the package have an identical composition; this includes estrogen and progesterone in equal proportions. The standard tablet contains 50 milligrams of estrogen (ethinyl esradiol), and the mini tablet contains 30 milligrams (the minimum dose required to inhibit ovulation).
Biphasic drugs
To avoid fairly frequent bleeding during the period of taking one package of mini-tablets, laboratories have developed estrogen-gestagen drugs with two phases of action and increasing dosages of estrogen and progesterone during the menstrual cycle, which provide two stages with increasing dosages or starting from the 8th tablet (7 one color + 14 another = 21 tablets), or starting from the 21st day (11 one color + 10 another color = 21 tablets).
Three-phase drugs
For several years now, a three-phase combination method has been used in France, combining separate rather than parallel administration of doses of estrogen and progesterone. In the first phase there is more estrogen, and in the second phase progesterone predominates. This chart was developed to reduce the likelihood of side effects such as venous bleeding or amenorrhea. The effectiveness of the drug is almost 100%.
Programmed tablet
It consists of absorbed estrogen, which is used for several days, and the remaining is a mixture of estrogen-progestogens. It is used in special cases not even for contraceptive purposes (for example, after cleansing). Efficiency is 99%.
There are three types of drugs:
- Microtablet - contains progestins in small doses of long-term action.
- The macropill is a long-acting progestin tablet containing a large dose of progestin, released from the 5th to the 25th day of the cycle.
- Injections. Instead of tablets, injections can be used. One intramuscular injection of 150 mg of progestin is sufficient to provide effective protection against pregnancy over the next 3 months. The 400 mg injection provides a 6 month guarantee. The principle of action of intramuscular injection has not yet been fully studied.
It can be compared with oral contraceptives: the injection slows down, the mucus at the cervix acquires special properties, becomes a barrier to sperm and prevents the attachment of a fertilized egg to the wall of the uterus.
In terms of effectiveness, this method is closer to the combined one.
These injections are indicated only in cases of urgent need; they are often given to people who are not able to take care of contraception themselves (in particular, the mentally ill).
The principle of action of hormonal contraception
Using various doses of the proposed substances in combination or separately, it is possible to inhibit ovulation and/or act on the cervical mucus, fallopian tubes, and uterine mucosa to prevent pregnancy.
Combined method
Used most often. Prevents pregnancy by blocking the ovulation process. During menstruation, estrogen levels decrease significantly, but there is enough of it to indirectly transmit a signal to the pituitary gland, which produces follicle-stimulating hormone (FSH).
This hormone causes the maturation of the oocyte, which begins to grow under its influence until the moment of ovulation and, leaving the phyllicle, moves along one of the tubes towards the sperm.
If, however, the follicle manages to mature, which means that it is not blocked enough because the estrogen level is too low, or because the pills were not used at all for one or several days. Ethinyl estradiol is used as estrogen, the dose of which ranges from 30 to 100 mcg. This substance inhibits ovulation by suppressing FSH.
- On the uterine mucosa - causes atrophy of the uterine mucosa and makes it unable to accept an egg.
- Mucus is the secret secretion of the cervix, which facilitates the passage of sperm from the vagina into the uterine cavity, under the influence of which it becomes an impenetrable barrier to the path of sperm.
- Finally, in addition to local action, progestin in combination with estrogen plays a central role in inhibiting the ovulation process. This double effect allows you to reduce the dose of estrogen introduced into the drug.
Preparations based on pure progestin
These are tablets containing only progesterone. How does it work? It is not yet known for sure. Progesterone should affect the consistency of the uterine mucus (the plug of secretions becomes denser and closes the entrance to the uterus more tightly, preventing sperm from penetrating the uterine passage). It also slows down the movement of the egg through the tubes and reduces the likelihood of sperm entering the egg.
The mucous membrane of maca is modified under its influence, and it becomes impossible for the egg to attach to the walls of the uterus.
The local effect of the progestin predominates when using a long-term microdosing method, while the general effect plays a decisive role in the intermittent and macrodose method.
The next-day pill is not exactly a contraceptive. This is not a hormonal drug that should be used for a specific, clearly limited period in case fertilization occurs during sexual intercourse. In this case, a set of measures is applied.
A large dose of estrogen should be taken within 48 hours after intercourse (2x25 mg distilbene or 5 mg ethinyl estradiol per day for 5 days). Due to poor tolerability, doctors recommend taking one classic combination tablet 2 times for 2 days with an interval of 12 hours. This changes the structure of the mucous membrane of the maca, which makes it impossible for the egg to attach to the wall and affects the mobility of the tubes. The end result of using this drug is the onset of menstruation.
Comparative analysis of the cycle with and without the use of tablets
Normal cycle | Combination Pill Cycle |
Day 1: Menstruation begins | Day 1: Menstruation begins. |
Day 5: In the ovary, the oocyte contained in the follicle begins to mature. It receives a hormonal (FSH) signal sent by the pituitary gland, which is “alarmed” by low estrogen levels at this point in the cycle. | Day 5: The 1st tablet is taken, containing synthetic female hormones, estrogens and progesterone. The tablet contains more estrogen than is usually present in the body on the 5th day (this amount is enough to prevent the pituitary gland from sending a signal, after which the oocyte begins to mature. Thus, taking a certain dose of estrogen for 21 days does not allow it to “sleep” condition. |
Days 12-13: There is a release of a small amount of progesterone, which causes ovulation. The estrogen level reaches certain values, a huge number of values are produced, a huge amount of luteinizing hormone (corpus luteum hormone) is produced, which precedes the breakthrough of a mature follicle and ovulation. | Day 6 and following: Continue taking pills daily. |
Day 14: The mature germ cell leaves the ovary and begins its four-day journey towards the uterus. Fertilization by sperm most often occurs during the 24-hour interval that the egg remains in the tube. The ruptured follicle is now called the “corpus luteum.” | Day 14: At the moment of ovulation, the germ cell does not enter the tube, and spermatozoa “look” for it in vain. A small dose of progesterone is enough to provide two important things: - Maintain the mucus plug in a thick and dense state, which makes it insurmountable for sperm. - Prevent the normal process of development of the mucous membrane lining the uterus in such a way that if the germ cell nevertheless manages to mature (if the level of estrogen is too low for a particular woman or if one day was accidentally missed in taking the pill) and fertilized, the egg still will not be able to attach to the wall of the uterus. |
Days 15-16: The corpus luteum continues to produce estrogens and progesterone for another 12 days to ensure the successful attachment of the egg to the wall of the uterus. Progesterone levels increase and reach maximum values on the 22nd day, which contributes to the fact that: — the mucous plug becomes denser and drier - the mucous membrane of maca is thicker and more nutritious (the uterine glands produce a sweet substance) |
Day 25: Taking the last pill. |
Days 27-28: If fertilization has not taken place, the corpus luteum produces very small amounts of estrogen and progesterone. In need of stimulation and hormonal support, the uterine mucosa begins to peel off. | Days 27-28: A sharp drop in estrogen and progesterone levels contributes to the detachment of the uterine mucosa. |
Day 29 (day 1): Menstruation begins. Estrogen levels drop again, as they do every month. This stimulates the pituitary gland to produce FGS, which is responsible for the development of the oocyte. A new cycle begins. | Day 29 (day 1): Menstruation begins. It is less abundant than in a woman who does not take the pill. This happens because progesterone contained in the contraceptive drug is present. |
Side effects of birth control pills
Effect on blood pressure
Synthetic estrogens used in contraception can increase blood pressure. In most cases, they do not increase it, but sharpen sensitivity and allow you to notice changes. If such an effect is detected, you should immediately stop taking this drug.
Some combinations of progestins in high doses can, but others have no noticeable effect. So, synthetic estrogens have an effect on blood pressure, the effect of which is enhanced by large doses of progestins.
Effect on glucose metabolism (blood sugar)
The main effect is exerted by synthetic estrogens. Progestins help only when used in medium to large doses. Small doses are practically harmless (such as microtablets).
Effect on lipid metabolism (increased levels of fats in the blood)
Estrogen-gestagen drugs mainly increase the level of triglycerides and cholesterol. New drugs are appearing on the market that have less or no effect on lipid metabolism. Microprogestins have a negligible effect: cholesterol levels do not increase, but triglysterides rather decrease slightly.
Effect on blood clotting
The introduction of estrogen entails hypercoagulation (the appearance of clots in the blood). Progestins have virtually no effect on clotting.
Cardiovascular complications
With the advent of oral contraceptives, many publications appeared in the press signaling an increase in the incidence of cardiovascular diseases in women taking them. However, most likely the pills only alleviated pre-existing health problems.
Women who became victims of thrombophlebitis were predisposed to vascular diseases (symptoms preceding vascular embolism; high blood pressure; lesions that promote thrombosis; problems with lipid metabolism; obesity; diabetes; hereditary vascular diseases; smoking; age).
The following diseases lead to death: thrombophlebitis, embolism of the respiratory tract, brain, especially the carotid artery, myocardial infarction.
The risk of vascular blockage by a blood clot increases with the use of estrogen-progestin drugs. It is associated primarily with the presence of estrogen and is reduced when using drugs containing small doses of it. The danger increases in the first month of taking the contraceptive, then the situation stabilizes.
The duration of use of the drugs does not matter. When you stop taking estrogen-progestin drugs for one month, the risk completely disappears.
The birth control pill and cancer
According to the World Health Organization, there is no evidence that estrogen-progestin drugs promote or reduce the risk of cancer in any part of the body.
If, before taking the contraceptive, a woman already had a malignant tumor or dysplasia (the presence of abnormally developing cells) in the uterine area, the pills can stimulate the development and increase in cancer cells that were “dormant” until that moment. Naturally, in such a situation, birth control pills are contraindicated.
The link between the words "cancer" and "birth control pill" came after it was discovered that cancer of the lining of the uterus occurred with sequential use of the pill. They were subsequently withdrawn from sale in the United States. No increase in cervical disease was reported. Epidemiological studies indicate that estrogen-progestin drugs may have beneficial effects in the treatment of benign breast tumors.
Oral contraceptives are among the most commonly used drugs. Since its introduction in the 1960s. they influenced the lives of many millions of people and changed society as a whole: for the first time in human history, a convenient, affordable and absolutely reliable method of contraception appeared, allowing family planning and avoiding unwanted pregnancies.
Before moving on to the pharmacology of hormonal contraceptives, we note a number of key points:
- hormonal contraceptives are one of the most effective drugs
- they differ significantly in composition, doses and side effects, but are comparable in effectiveness,
- these drugs have additional beneficial effects,
- Due to the difference in drugs and doses used for hormonal contraception and hormone replacement therapy, the side effects in both cases are also different. In most cases, oral contraceptives are completely reliable and well tolerated.
Historical reference
At the turn of the 19th and 20th centuries, a number of European scientists (including Beard, Prenan and Loeb) suggested that the corpus luteum secretes a substance that suppresses ovulation during pregnancy. At first, this concept was largely theoretical, but the Austrian physiologist Haberlandt developed it further by proposing the use of hormones for contraception (Regope, 1994). In his work “On the Hormonal Sterilization of Female Animals,” he described temporary infertility in female rodents whose food was supplemented with ovarian and placental extracts, a clear example of the use of oral contraceptives (Haberlandt, 1927). Shortly after the isolation of progesterone from the corpus luteum, the purified hormone was shown to prevent ovulation in rabbits (Makepeace et al., 1937) and in rats (Astwood and Fevold, 1939).
In the 1950s it was found that progesterone and 19-norprogestogens disrupt ovulation in women (Rocketal., 1957). It is curious that these data were obtained from attempts to treat infertility with progestogens or a combination of progestogens with estrogens. In both cases, ovulation was prevented in the majority of women, but due to the risk of carcinogenic effects and other side effects of estrogens (diethylstilbestrol was used), only progestogens were subsequently used.
Among the progestogens, norethinodrel was one of the first to be tested, but at first it contained an admixture of mestranol. After clearing mestranol, it turned out that norethinodrel more often causes uterine bleeding and does not always suppress ovulation. The drugs were again combined, and the first large clinical trial of combined oral contraceptives was conducted with this combination.
Research conducted in the second half of the 1950s. in Puerto Rico and Haiti, showed almost 100% effectiveness of the combination drug mestranol/norethinodrel (Pin-, with us et al., 1959). In late 1959, the drug was approved by the FDA and became the first hormonal contraceptive approved for use in the United States; in 1962, a second drug appeared - mestranol/norethisterone. By 1966, a dozen similar drugs (1st generation) were already in use, including mestranol or ethinyl estradiol in combination with one of the 19-norprogestogens. In the 1960s Minipills and progestogen-only implantable contraceptives have also been developed. These drugs quickly became widespread in many countries, but were not approved in the United States until the 1990s.
Millions of women began taking oral contraceptives, but in the 1970s... There have been numerous reports of their side effects (Kols et al., 1982). When it became clear that these effects were dose dependent and that estrogens and progestogens were synergistic in suppressing ovulation, hormone doses were reduced. This is how 2nd generation oral contraceptives appeared. The rise of two- and three-phase combination drugs in the 1980s. allowed us to further reduce the dose of hormones; Perhaps, modern drugs contain minimal doses of estrogens and progestogens sufficient for reliable contraception. In the 1990s. In Europe and then in the USA, 3rd generation drugs appeared containing progestogens with reduced androgenic activity (norgestimate and desogestrel; gestodene is also used in Europe). Finally, in the 1980s. It became clear that oral contraceptives have additional beneficial properties (Kolset al., 1982).
Types of hormonal contraceptives
These drugs contain estrogens and progestogens. In the United States, they are used most often as a means of contraception. Their theoretical efficiency is estimated at 99.9%, while the actual efficiency is 97-98%. These drugs contain ethinyl estradiol (occasionally mestranol) and any 19-norprogestagen from the group of estrans or gonans. All progestogens, to one degree or another, have androgenic, estrogenic and antiestrogenic activity, which explains some of their side effects. Compared to other 19-norprogestogens, the newest drugs in this group, desogestrel and norgestimate, have less androgenic effects (Shoupe, 1994; Archer, 1994; Rebar and Zeserson, 1991). The pharmacokinetics of estrogens and progestogens is described above.
There are mono-, two- and three-phase combined oral contraceptives. The first contain a constant ratio of estrogens and progestogens, they are taken for 21 days, one tablet per day with a break of 7 days (usually the package contains 28 tablets, the last 7 tablets are placebo). Two- and three-phase preparations include 2 or 3 types of tablets with different ratios of estrogens and progestogens, the tablets are taken sequentially for 21 days. This reduces the total dose of hormones and better reflects the normal ratio of estrogens and progestogens during the menstrual cycle, including their higher concentrations in the luteal phase. Two- and three-phase combined oral contraceptives were developed in the 1980s, primarily to reduce the dose of progestogens, when evidence of their adverse effects on the cardiovascular system became available. In 2000, the FDA approved estradiol/medroxyprogesterone, a parenteral contraceptive administered once a month.
The ethinyl estradiol content in modern oral contraceptives is 20-50 mcg, usually 30-35 mcg. At a dose of 35 mcg or less they talk about modern, or low-dose, drugs. Due to the different activities of progestogens, their doses fluctuate within a wider range. Thus, monophasic drugs used in the USA contain 0.4-1 mg of norethisterone, 0.1-0.15 mg of levonorgestrel, 0.3-0.5 mg of norgestrel, 1 mg of ethynodiol, 0.25 mg of norgestimate or 0.15 mg of desogestrel; in two- and three-phase preparations the doses are slightly different. The first oral contraceptive (Enovid) contained 10 mg of norethinodrel and 150 mcg of mestranol. In 1966, most drugs contained 50-150 mcg of estrogens and 2-10 mg of progestogens. Significant differences in doses do not allow data on the side effects of 1st generation drugs to be transferred to modern oral contraceptives.
In terms of reliability, these drugs are somewhat inferior to combination drugs: their theoretical effectiveness is 99%, actual - 96-97.5%. These include: 1) mini-pills (capsules with low doses of progestogens - 350 mcg of norethisterone or 75 mcg of norgestrel), they are taken orally continuously, 1 capsule per day, 2) implantable contraceptives (for example, containing 216 mg of levonorgestrel), slowly releasing drug and providing contraception for 5 years, 3) suspension of crystalline medroxyprogesterone for intramuscular administration (single dose is 150 mg), providing contraception for 3 months.
Intrauterine contraceptives have been developed that slowly release progesterone; they are changed once a year. The effectiveness of the drug is 97-98%; the contraceptive effect is associated with the local effect of the hormone on the endometrium.
Postcoital contraceptives
Previously for postcoit-. high doses of diethylstilbestrol and other estrogens (morning after pills) were used for contraception, but this method was never approved by the FDA. Based on clinical trials (Task Force on Postovulatory Methods of Fertility Regulations, 1998), levonorgest-rel (tablets containing 0.75 mg of the drug, taken orally 2 times with an interval of 12 hours) and ethinyl estradiol were approved for post-coital contraception. levonorgestrel (tablets containing 0.05 mg and 0.25 mg of drugs, respectively, taken 2 times 2 tablets with an interval of 12 hours). Essentially, we are talking about the use of oral contraceptives in high doses, and, according to the FDA, the use of other drugs of similar composition is safe and effective for postcoital contraception.
The drug should be taken for the first time no later than 72 hours after sexual intercourse and again after 12 hours. The probability of pregnancy is reduced by 4 times: in the absence of contraception it is 8% (with sexual intercourse in the 2-3rd week of the menstrual cycle ), and when using postcoital contraceptives it decreases to 2%.
Mechanism of action
Combined oral contraceptives
These agents act by suppressing ovulation (Lobo and Stanczyk, 1994). Against this background, serum concentrations of LH and FSH decrease, the rise in LH in the middle of the cycle disappears, and the synthesis of endogenous estrogens and progesterone decreases; As a result, ovulation does not occur. In certain cases, progestogens and estrogens separately have the same effect, but their combination reduces the serum concentration of gonadotropic hormones and suppresses ovulation more reliably.
Due to the complex feedback system in the hypothalamic-pituitary-gonadal axis, the suppression of ovulation by oral contraceptives appears to have several causes. In addition, long-term use of these drugs may involve additional mechanisms that are not characteristic of the normal menstrual cycle. Obviously, the exceptionally high effectiveness of these drugs is due to the multiple mechanisms of action.
The main role in the action of oral contraceptives is played by their effect on the hypothalamus. Progesterone sharply reduces the frequency of impulse secretion of GnRH, and since ovulation requires a certain frequency, this effect apparently plays a major role in the contraceptive effect. Estrogens do not affect the frequency of pulsed secretion of GnRH in monkeys and women with a normal menstrual cycle, but in its long-term absence (in monkeys with ovaries removed and in postmenopausal women), estrogens noticeably reduce the frequency of rhythmic activation of hypothalamic neurons, and progesterone enhances this effect ( Hotchkiss and Knobil, 1994). Theoretically, this effect of estrogen on the hypothalamus may be important during long-term use of oral contraceptives.
Obviously, the effect on the pituitary gland is also important. While taking oral contraceptives, the administration of GnRH increases the serum concentration of LH. However, this increase is much less than in the absence of oral contraceptives; consequently, the latter reduce the sensitivity of the pituitary gland to GnRH (Mishell et al., 1977). Normally, estrogens in the follicular phase inhibit pituitary FSH secretion, which may contribute to the suppression of follicular growth observed with oral contraceptives. A prolonged increase in the serum concentration of estrogen also causes the LH surge necessary for ovulation in the middle of the menstrual cycle. Progesterone during the natural menstrual cycle does not affect this process, but taking progestogens suppresses the estrogen-induced LH surge. Thus, the varied effects of estrogens and progestogens on the pituitary gland contribute to the action of oral contraceptives.
Perhaps suppression of ovulation is not the only mechanism of action of oral contraceptives. They apparently disrupt the movement of sperm, egg and embryo through the fallopian tube, which is so important for pregnancy. In addition, under the influence of progestogens, the glands of the cervix secrete dense viscous mucus, which impedes the penetration of sperm, and endometrial restructuring occurs, preventing implantation of the embryo. However, against the background of suppressed ovulation, it is difficult to quantify the contribution of these mechanisms.
Progestogen contraceptives
Doses of progestogens contained in minipills and implantation contraceptives suppress ovulation only in 60-80% of cases, and the effect of these drugs is associated mainly with an increase in the viscosity of cervical mucus, which impedes the penetration of sperm, and changes in the endometrium, which prevent implantation of the embryo. Injections of medroxyprogesterone suspension also have a similar effect, but also provide a serum concentration of the drug sufficient to almost completely suppress ovulation. The latter effect is associated with a decrease in the frequency of impulse secretion of GnRH, which prevents the LH surge necessary for ovulation.
Postcoital contraceptives
The action of these drugs is associated with various mechanisms. There is some evidence that when used in the first half of the menstrual cycle, they delay or suppress ovulation, but this alone is probably not enough to explain their high effectiveness. Other, somewhat controversial mechanisms include effects on the endometrium with disruption of embryo implantation, inhibition of the function of the corpus luteum necessary for maintaining pregnancy, increased viscosity of cervical mucus, disruption of the movement of sperm, eggs and embryos through the fallopian tube, and disruption of fertilization. One way or another, after embryo implantation, postcoital contraceptives do not work.
Side effects
Combined oral contraceptives
Soon after the introduction of these drugs, evidence of their side effects began to accumulate (Kols et al., 1982). Many of the effects were dose dependent, leading to the development of modern low-dose hormonal drugs. 1st generation drugs caused dysfunction of the cardiovascular system (including increased blood pressure, myocardial infarction, hemorrhagic and ischemic stroke, deep vein thrombosis and pulmonary embolism), breast, liver and cervical cancer, as well as a number of endocrine and metabolic disorders. Modern oral contraceptives are reasonably safe (unless contraindicated) and provide additional benefits (Baird and Glasier, 1993).
The cardiovascular system
Reducing the dose of hormones in modern drugs has markedly improved their safety (Baird and Glasier, 1993; Mischell, 1999; Castelli, 1999; Sherif, 1999). In the absence of risk factors for atherosclerosis (primarily smoking), these drugs do not affect the risk of myocardial infarction and stroke. The risk of pulmonary embolism increases, but the absolute increase in the number of such cases is small (approximately 50% of that during pregnancy), since in the absence of additional risk factors, pulmonary embolism occurs extremely rarely. However, against the background of smoking and other predisposing factors, this increase increases (Castelli, 1999). 1st generation oral contraceptives increased blood pressure in 4-5% of healthy women and in 10-15% of women with arterial hypertension. With the use of modern drugs, these figures are much lower, and most studies have not revealed a significant change in blood pressure. After discontinuation of oral contraceptives, the risk of cardiovascular complications appears to return to baseline.
In 1995, there were reports in Europe that 3rd generation oral contraceptives containing gestodene and desogestrel significantly increased the risk of PE compared with drugs containing levonorgestrel and norethisterone, but subsequent analysis attributed the differences to factors unrelated to the composition of the drugs ( Barbieri et al., 1999). In general, the various progestogens included in modern oral contraceptives have approximately the same effect on the cardiovascular system.
As mentioned above, estrogens increase the concentration of HDL and reduce the concentration of LDL, while progestogens act in the opposite way. According to recent data, modern oral contraceptives do not significantly affect the concentrations of total cholesterol, HDL and LDL, but slightly increase the concentration of triglycerides.
Malignant neoplasms
It was thought that due to the mitogenic effect of estrogens, oral contraceptives may increase the risk of cancer of the uterus, ovaries, breast and other organs. Moreover, in the late 1960s. There was evidence of endometrial dysplasia associated with sequential contraceptives, and these drugs were banned in the United States. But oral contraceptives have now been shown to have no significant effect on the risk of cancer (Baird and Glasier, 1993; Sherif, 1999; Westhoff, 1999).
Combined oral contraceptives even reduce the risk of uterine cancer by 50%, and this effect persists for 5 years after their discontinuation. This effect is associated with progestogens, which block the mitogenic effect of estrogens throughout the entire cycle (21 days) of their administration. Likewise, the risk of ovarian cancer is reduced, which may be explained by less stimulation of the ovaries by gonadotropins.
An increased risk of adenoma and liver cancer has been reported, but these are quite rare diseases, and determining their risk with oral contraceptives is complicated by many factors. There is evidence of an increased risk of cervical cancer, but it is difficult to identify a clear connection between this disease and the use of oral contraceptives.
The main concerns about the carcinogenic effects of oral contraceptives relate to breast cancer. In women of childbearing age, the risk of this tumor is low and, according to numerous studies, when taking modern medications, it increases by only 10-20%, depending on additional factors. The increase in incidence depends little on the duration of taking the drug, its composition, the age at which it was started, and the number of births. It is important that 10 years after stopping oral contraceptives, the risk of breast cancer is the same as in women who have never received them. In addition, breast cancer in women taking these drugs is more often detected in the early stages, without lympho- and hematogenous metastases, and is better treatable (Westhoff, 1999). In general, oral contraceptives have little effect on your lifetime risk of breast cancer.
Metabolism
Estrogens and progestogens have ambiguous effects on glucose metabolism and insulin sensitivity; it may differ among drugs of the same group, for example among 19-HopnporecTareHOB (Godsland, 1996). 1st generation contraceptives generally impaired glucose tolerance, increasing glucose and insulin concentrations both in the fasting state and after an oral glucose tolerance test. With decreasing doses of hormones, these effects weakened, and modern drugs can even improve insulin sensitivity. In addition, high doses of progestogens in 1st generation drugs increased LDL concentrations and decreased HDL concentrations, but modern drugs do not have this effect (Sherif, 1999). There have been reports of an increased risk of gallstone disease; Obviously, it increases slightly and only during the period of taking oral contraceptives and with long-term use (Grodstein et al., 1994).
Estrogens promote the synthesis of a number of plasma proteins in the liver, including thyroxine-binding globulin, transcortin and sex hormone-binding globulin. Through feedback mechanisms, this leads to an increase in the synthesis of the corresponding hormones, which normalizes the concentrations of free hormones. However, total hormone concentrations are increasing, which may complicate the interpretation of diagnostic samples that measure total plasma hormone concentrations.
Ethinyl estradiol, which is part of some oral contraceptives, causes a dose-dependent increase in the concentration of a number of coagulation factors. In healthy non-smoking women, fibrinolytic activity simultaneously increases, so in general, blood clotting remains almost unchanged. However, in smokers this compensatory effect is reduced, which may shift the balance towards increased clotting (Fruzzetti, 1999).
Other side effects
Possible nausea, swelling, mild headache; Severe migraine occurs occasionally. Bleeding is sometimes observed in the first 21 days of the cycle when medications are taken. In some cases, no menstrual-like bleeding occurs during a 7-day placebo intake, and the woman may think that she is pregnant. Weight gain, acne and hirsutism that sometimes occur are associated with the androgenic activity of 19-norprogestogens. Progestogen contraceptives. Irregular spotting and bleeding from the genitals are the most common side effects and the main reason for stopping all three types of these drugs. Over time, the risk of bleeding decreases, especially with long-acting medications; After a year of use, amenorrhea often occurs.
Mini-pills do not increase the risk of thromboembolic complications (this effect of combined oral contraceptives is associated with estrogens), do not affect blood pressure and do not cause pain in the mammary glands and nausea. Due to the androgenic activity of progestogens (for example, norethisterone), acne may occur. Progestogen-based contraceptives are preferable for nursing mothers, since, unlike combined preparations containing estrogens, they do not suppress lactation.
Headache is the second most common side effect (after bleeding) that occurs after injection of medroxyprogesterone suspension. Raedra-vitality and weight gain have also been reported, but there is no clinical trial data on this. Another thing is more dangerous - a number of studies have found a decrease in the concentration of HDL and an increase in the concentration of LDL; There is also evidence of a decrease in bone density. This may be due to the suppression of estrogen synthesis, since medroxyprogesterone particularly strongly reduces the concentration of gonadotropic hormones. In one early study, medroxyprogesterone caused mammary cancer in dogs, but this was later found to be due to species-specific metabolism of the drug to estrogen.
Numerous clinical trials have not found an increased risk of cancer of the pouch, ovary, body and cervix in women receiving medroxyprogesterone. Complete elimination of the drug takes a long time, and the contraceptive effect can persist for 6-12 months after injection.
Implantable contraceptives can cause infection, irritation and pain at the site of insertion under the skin, and occasionally the implant will be rejected. Sometimes headache, irritability, weight gain are observed; Acne causes great inconvenience for some patients. Metabolic studies with levonorgestrel implants in most cases revealed only minimal changes in lipid, carbohydrate and protein metabolism and blood biochemical parameters. After removal of the implant, ovulation is quickly restored: in half of women - within 3 months, in 90% of cases - within a year.
Postcoital contraceptives. These drugs most often cause nausea and vomiting: ethinyl estradiol / levonorgestrel - in 50 and 20% of women, respectively, levonorgestrel - in 23 and 6% (Task Force on Postovulatory Methods of Fertility Regulation, hash Although there is no data on increased blood clotting with ethinyl estradiol / levonorgestrel, this effect is inherent in combined contraceptives, therefore, in case of risk factors for pulmonary embolism (smoking, history of thrombosis), it is preferable to prescribe only levonorgestrel.In confirmed pregnancy, postcoital contraceptives are contraindicated.
Contraindications
Modern oral contraceptives are quite safe for most healthy women, but under certain predisposing factors they can increase the risk and severity of a number of diseases. Absolute contraindications I thromboembolic diseases (currently or in history), coronary artery disease, myocardial infarction, cerebral artery atherosclerosis, primary dyslipoproteinemia, breast cancer or suspicion of it, malignant neoplasms of the genital organs and other hormone-dependent tumors, unclear bleeding from the genitals etiologies, confirmed or possible pregnancy, liver tumors (even remote ones) and liver failure. The risk of myocardial infarction and stroke is especially high in women over 35 years of age who smoke more than 15 cigarettes per day; Even drugs with low doses of hormones are contraindicated for them.
Relative contraindications are migraine, arterial hypertension, diabetes mellitus, cholestasis in pregnancy, cholestasis during previous use of oral contraceptives and cholelithiasis. Many recommend stopping these medications 3-4 weeks before elective surgery to reduce the risk of thromboembolic complications. If there is a history of uterine fibroids and gestational diabetes, oral contraceptives are prescribed with caution; only drugs with low hormone content are acceptable.
Mini-pills are contraindicated in cases of bleeding from the genital organs of unknown etiology, tumors and other liver diseases, and breast cancer or suspected cases of it. Injections of medroxyprogesterone suspension and implants with levonorgestrel are contraindicated, in addition, in thrombophlebitis and other thromboembolic diseases, as well as in the presence of risk factors for these conditions.
Choice of drug
A wide variety of drugs and dosages makes it possible to individually select hormonal contraceptives. The general consensus is that you should start with the minimum doses of hormones that provide reliable contraception. Typically, the drug should contain 30-35 mcg of ethinyl estradiol, but for thin women and women over the age of 40, 20 mcg is sometimes sufficient (the same dose has recently been used to treat menstrual disorders in pre-menopause). For obese women, a drug containing 50 mcg ethinyl estradiol may be required. A low estrogen to progestogen ratio sometimes leads to uterine bleeding due to uneven proliferation of the endometrium; in such cases, a drug with a higher dose of estrogen is indicated.
In case of contraindications to estrogens, you can resort to progestogen contraceptives. The effectiveness of mini-pills is especially high in certain categories of women, for example, those who are breastfeeding or those over 40 years of age. when fertility is reduced. Unlike estrogens, progestogens do not inhibit lactation.
It is necessary to take into account the effect of other drugs that accelerate the metabolism of estrogens (rifampicin, barbiturates, phenytoin) or disrupt their enterohepatic circulation (tetracyclines, ampicillin). Antimicrobial agents can suppress the intestinal microflora, which forms the enzymes necessary for the hydrolysis of conjugates excreted in bile and the reabsorption of estrogens. In such cases, serum estrogen concentrations decrease and the effectiveness of low-hormone drugs is less than the theoretical 99.9%.
The choice of drug may also depend on the progestogen it contains - this is due to differences in the antiandrogenic and other properties of 19-norprogestogens. The androgenic activity of progestogens can contribute to weight gain, acne (due to increased secretion of the sebaceous glands) and dyslipoproteinemia. Modern drugs with low hormone content are largely devoid of this side effect, but if it does occur, switching to a drug containing a progestogen with less androgenic activity can help. Among the progestogens included in oral contraceptives, the androgenic properties are most pronounced in norgestrel, in norethisterone and ethynodiol they are moderate, and in desogestrel and norgestimate they are minimal.
A triphasic oral contraceptive with low levels of ethinyl estradiol and norgestimate is approved by the FDA for the treatment of moderate acne in girls over 15 years of age who wish to avoid pregnancy. Similar drugs containing ethynodiol and desogestrel also help. Their action is associated with increased synthesis of sex hormone-binding globulin, which causes a decrease in the concentration of free testosterone in the plasma while maintaining a constant concentration of total testosterone (Redmond et al., 1997).
Thus, the effectiveness and tolerability of various hormonal contraceptives varies among women. The choice is very wide, and changing the drug can help reduce side effects without affecting the reliability of contraception.
Additional benefits of oral contraceptives
Already in the 1980s. Additional benefits have been found for combined oral contraceptives (Kols et al., 1982; Goldzieher, 1994; Baird and Glasier, 1993), including reducing the risk of ovarian and uterine cancer, preventing menstrual irregularities and several other diseases.
The risk of ovarian and uterine cancer decreases within 6 months after starting oral contraceptives; after 2 years it is halved. Moreover, the protective effect persists for almost 15 years after discontinuation of the drug. In addition, oral contraceptives prevent the development of ovarian cysts and fibrocystic mastopathy.
Oral contraceptives have a beneficial effect on the menstrual cycle. For many women, it becomes more regular and bleeding decreases.
Opponents of the use of contraceptive drugs for animals claim
owners of cats and dogs that even a single use of a hormonal drug
will lead to inevitable health problems. Pets to whom owners give
hormonal agents predict cancer and inflammatory
processes of the reproductive organs.
Let's figure out who can actually be to blame for animal diseases and what
do so as not to harm your pet.
Think about it: cases of cancer are one in a thousand, and contraceptives for cats and dogs
millions are used.
The real causes of cancer in animals
- Poor quality food;
- Unfavorable environmental conditions.
- Chronic stress in the animal (due to constant empty estrus, prolonged
being alone at home); - Incorrect use of hormonal contraceptives.
However, “droplets from estrus” is the veterinarian’s simplest answer about the reasons
similar diseases. The essence of the problem is hidden much deeper.
What are CONTRACEPTIVES actually?
A fictitious division of contraceptive drugs into
"natural" and "chemical". This division is not typical for veterinary medicine.
pharmacology.
“NATURAL” PREPARATIONS or, as opponents of their use call them
contraceptives, “herbal teas” are not contraceptives. They are not intended for
regulation of sexual hunting in animals and are not able to prevent unwanted
pregnancy.
ABOUT "CHEMICAL" PREPARATIONS. There are two “chemical” drugs
varieties: monohormonal and bihormonal agents. Among the first are one
hormone, the latter contains two hormones. And this is of fundamental importance, here
Why.
Monohormonal drugs appeared at the dawn of contraception for pets,
in the 90s. These drugs use only one type of hormone (megestrol
acetate). To achieve the necessary calming effect, the drug contains:
its high concentration. This increases the risk of impact on the animal’s body. Bihormonal drugs were developed 15 years ago. Unlike
Monohormonal drugs contain two hormones -
analogues of natural sex hormones in animals. Presence of two hormones
allows you to significantly reduce their concentration and delicately adjust
hormonal background of the animal, taking into account its species and gender. To calm this animal
quite enough.
Choose the right path
Decide if your cat really needs to preserve her reproductive health.
function? Your cat has no breed value and is not intended for
breeding? You don't have the time or desire to monitor your pet's heat cycles, and you don't
Can you give him contraception on time? Possibly a solution to problems
unwanted behavior of a pet during sexual hunting - this is sterilization or
castration.
If surgery is unacceptable for your animal for one reason or another, and
It is still necessary to calm down a pet that has gone on a spree, adhere to the following
rules:
1. Consult your veterinarian before starting to take the drug,
check the health of the animal;
3. Read the instructions carefully;
2. Choose the drug strictly according to the type and gender of your animal (feline, male, female or
male);
4. Calculate the dosage correctly - according to the weight of the pet and depending on the problem,
which needs to be resolved;
5. If your cat has already gone on a spree, it is important to start using the drug NOT
LATER THAN 2 DAYS from the start of sexual heat. The “estrus interruption” scheme does not
suitable for constant use, use it NO MORE THAN 2 TIMES A YEAR;
6. If you want your cat to remain CALM ALL YEAR LONG,
use the CALMING EFFECT MAINTENANCE SCHEME. Start off
The drug should be used during sexual rest, regularly, once every 7-14 days.
depending on the drug chosen. To prevent the cat from asking for the cat, use this
scheme throughout the year, take a break after 18 months. The described schemes of use are in the instructions for any contraceptive
drug. The owner can only read them carefully.
The problem of preventing unwanted pregnancy has been troubling humanity for a long time. And today, family planning remains one of the most pressing topics. Contraception is protection against unwanted pregnancy, and therefore against the negative consequences that may arise as a result of its interruption. Any method of preventing pregnancy is safer for a woman’s health than terminating it! According to the Russian Medical Academy, only 25% of married women use contraception; in recent years, the use of the most effective methods of contraception, such as hormonal and intrauterine devices, has decreased by 1.5 - 2 times!
Over the long century of its existence, hormonal contraception has acquired myths and legends, which force women to be wary of using it. Let's try to figure it out, is this true?
How long has hormonal contraception been around?
The idea of its creation arose at the beginning of the twentieth century thanks to the experiments of the Austrian doctor Haberland. The first artificially synthesized female sex hormones - estrogen and progesterone - were obtained in 1929 and 1934, and in 1960, the American scientist Pincus created the Enovid pill, which marked the beginning of the entire type of hormonal contraception.
What are hormonal contraceptives?
They consist of estrogen and progestogen components, artificially created twin brothers of estrogen and progesterone (natural sex hormones in women). Such drugs are called combination drugs. Sometimes drugs containing only gestagens are used.
What types of hormonal contraception are there?
Hormonal contraception is divided into oral (OK) - the drug enters the woman’s body through the mouth in the form of tablets and parenteral - hormones enter through other routes, bypassing the intestines. Another type of parenteral hormonal contraception is special ring, placed into the vagina by the woman herself once a month. There is also a special type of intrauterine device, which has a contraceptive effect due to the release of hormones.
What is COC?
COCs are combined oral contraceptives (analogues of estrogen and progesterone in tablets).
Distinguish monophasic COCs (in each tablet of the drug the content and ratio of estrogen and progesterone are the same), two-phase (the estrogen content is the same in all tablets, but the dose of progesterone in the second phase of administration is higher), three-phase (different ratio of hormones in the three phases of administration).
Besides, COCs, depending on the dose of estrogen, are divided into high-dose, low-dose and micro-dose. From the first days of the invention of these drugs to improve COCs, scientists have been following the path of reducing hormone dosages: it is believed that the lower the dosage in a COC tablet, the fewer side effects.
Are three-phase COCs more physiological and closer to the normal menstrual cycle?
Triphasic COCs do not necessarily mimic the hormonal fluctuations of the normal menstrual cycle and are not more physiological than monophasic COCs. The advantage of the former is a lower percentage of side effects than the others. But only a few women tolerate triphasic COCs themselves well.
How do COCs work?
The hormones included in COCs affect the process of formation and release of the egg from the follicle in the ovary in such a way that ovulation simply does not occur. That is, the egg is not “born”, therefore, its meeting with the sperm is obviously impossible. It is also impossible because COCs create a kind of trap for male reproductive cells. These drugs make the cervical mucus more viscous, which is a barrier to the path of sperm into the uterus.
In addition, even if fertilization of the egg does occur, for further development it is necessary that it enter the uterine cavity at a certain moment - not earlier and not later than the due date. Under the influence of COCs, the work of the fallopian tubes, which “move” the fertilized egg towards the uterus, slows down, thereby preventing the progression of pregnancy.
Let's say that the fertilized egg managed to get into the uterus at the right moment. But for the further development of the embryo, a special condition and structure of the inner lining of the uterus (endometrium) is necessary, which provides nutrition and other conditions necessary for pregnancy. When taking COCs, changes occur in the structure of the endometrium that prevent the further development of the fertilized egg.
What are the rules for taking COCs?
The drug should be taken on one of the first days of menstruation or within three days after an abortion. The earlier the better. If the use of COCs did not start on the first day of the cycle, it is better to use additional methods of contraception during the first two weeks. Reception is continued for 21 days, after which a break of no more than 7 days is taken. Typically, a woman is recommended to take COCs at the same time of day, and so that she does not forget about it, it is better if she associates taking the drug with a daily ritual, for example, putting the pills next to her toothbrush.
If a woman nevertheless forgets to take the next pill (the most common mistake in taking COCs), it is recommended to take it as soon as possible and continue taking the subsequent ones as usual. But in this case, additional contraception for 2 weeks is desirable.
How many months (years) in a row can you use COCs?
There is no clear opinion on this matter. Some gynecologists believe that if the drug is selected correctly, the duration of its use does not increase the risk of complications. Therefore, you can use this method of contraception as long as necessary, until the onset of menopause. Taking breaks from taking medications is not only unnecessary, but also risky, since during this period the likelihood of an unwanted pregnancy increases.
Other scientists take a different point of view, insisting on small but mandatory breaks of 3-6 months. So, some recommend simulating a natural pregnancy, that is, taking COCs for 9 months, and then stopping the drug for 3 months, using other methods of contraception. The body is given a kind of rest from the “rhythm and doses of hormones imposed on it.” There is evidence that with continuous use of COCs for a number of years, the ovaries seem to become exhausted, in other words, they “forget” how to work independently.
How effective are COCs?
This method of contraception is highly reliable in preventing unwanted pregnancy. According to statistics, within twelve months of their use, 1000 women experience 60-80 pregnancies, but only one is the result of insufficient contraceptive effect of the drug, and the rest are due to errors in the use of COCs. For comparison: with interrupted sexual intercourse during the year, there are 190 cases of unplanned pregnancy per 1000 women, of which 40 are due to the unreliability of the method itself.
How long after stopping taking COCs can a woman become pregnant?
With proper use of COCs, the ability to conceive is restored immediately after discontinuation of COCs. After 3-6 months it reaches 85%: the same as in women who did not use hormonal contraception.
How does OK affect libido?
There is no definite answer, everything is individual. But most women note an increase in sexual desire, since there is no fear of an unwanted pregnancy when taking OCs. If there is a decrease in sexual desire when using COCs, then this problem can sometimes be solved by changing the contraceptive used to another one with less progesterone.
Do OCs actually make you fat?
The fear of gaining weight from hormonal pills has existed for a long time. Weight gain (usually plus 2-3 kg) occurs in the first three months of taking the drug, mainly due to fluid retention in the body. OCs can increase appetite, which also contributes to weight gain. However, in other women, taking OCs, on the contrary, causes the loss of extra pounds or does not affect weight at all.
Can young nulliparous girls take OK?
In some cases, even teenage girls are prescribed OCs by gynecologists, since these drugs, in addition to preventing unwanted pregnancy, have a number of medicinal properties.
When are OCs prescribed as treatment?
For various menstrual irregularities, for some uterine bleeding, for polycystic ovary syndrome, as well as for the treatment of severe forms of premenstrual syndrome, endometriosis, etc. There is also evidence that COCs have a positive effect on the course of gastric ulcers and rheumatoid arthritis.
Are COCs really prescribed for the treatment of infertility?
Hormonal contraceptives: truth and myths
For some forms of endocrine infertility, “intermittent use” of OCs is used. For example, taking some of these drugs for 3 months followed by a break of 2 months in certain cases restores ovulation.
Who are these drugs prescribed to?
In the absence of contraindications to taking hormones, COCs are recommended for women of any age who want to protect themselves from unwanted pregnancy.