Birth control pills after the act: types, dosages, rules of use
Despite a large list of developed reliable methods of preventing unwanted pregnancies, sometimes due to recklessness or sexual violence a woman has to resort to emergency contraception. One of these includes contraceptive pills after unprotected intercourse, components of which are hormone analogues or hormone-like substances. Take these medications with caution, as they pose a danger to women's health and can cause problems with the onset of pregnancy in the future.
Content:
- Types of drugs and the mechanism of their action
- Indications for emergency contraception
- Mode of application
- The negative consequences of birth control pills
- Contraindications

Types of drugs and the mechanism of their action
As a means of emergency contraception, that is, protection from pregnancy after sex, when the probability of conception is quite high, the following drugs are used:
- tablets containing levonorgestrel (postinor, escapel);
- tablets based on mifepristone (mifepristone, miropristone, ginepristone, mifegin);
- high (ovidone, non-vellon, antevine) and low-dose (yarina, regulon, marvelon, microgonone, femodenum, janin) monophasic combined oral contraceptives (COCs).
Preparations of levonorgestrel
The active substance of postinor tablets and the levonorgestrel escapel belongs to synthetic progestogens. The mechanism of contraceptive effect is realized due to:
- inhibition and suppression of ovulation (release of the egg from the dominant follicle );
- changes in the structure of the inner layer of the uterus, exclusion of the conditions necessary for the successful implantation of a fertilized egg and its further development;
- Reduction of the peristalsis of the fallopian tubes, slowing the movement of the egg into the uterus;
- increasing the viscosity of cervical mucus, creating a mechanical obstacle for the promotion of spermatozoa.
The more time passed after unprotected sexual intercourse, the less effective are the tablets with levonorgestrel for preventing unwanted conception. If the process of implantation of a fertilized egg has already occurred, then their use does not prevent the normal development of pregnancy. According to statistical data, when taking levonorgestrel within 24 hours after sexual intercourse, the effectiveness is 95%, 24-48 hours - 85%, and after 48-72 hours - only 58%.
Important: To protect against pregnancy after unprotected intercourse, in addition to tablets, IUDs are also used, the installation of which is performed for these purposes within 120 hours after coitus.
Preparations based on mifepristone
Mifeferiston is a synthetic anti-progestagenic agent of the steroid structure. Tablets on its basis have a complex effect:
- disrupts the functioning of the yellow body ;
- cause delamination of the endometrium;
- block the receptors of the main hormone of pregnancy of progesterone located in the endometrium, which prevents its normal development after implantation of the oocyte;
- increase the contractile activity of the muscular layer of the uterus, myometrium, due to an increase in its sensitivity to prostaglandins.
Mifepristone and its analogues cause in the body female expulsion from the uterus of the fetal egg and are the means of medical abortion in the early stages. After taking a lot of bleeding, it is necessary to use them strictly under the supervision of a doctor. For termination of pregnancy, mifepristone is used for up to 7-9 weeks.
Combined oral contraceptives
After unprotected sexual contact, COCs containing estrogen and progestogen commonly used for routine contraception are sometimes used. Their effectiveness is 75-80%, which is much lower than that of Postinor and Escapel. In addition, when taking high doses of hormones, there is a significant increase in the likelihood of serious side effects, so many doctors prefer tablets with levonorgestrel.
The advantage of this group of contraceptive pills is a wide selection of drugs.
Interestingly: The use of COCs to prevent pregnancy after sexual contact has been called the Yuzpe method in honor of the Canadian doctor Albert Yuzpe, who developed this method of contraception in 1977.
Indications for emergency contraception
Contraceptive pills for emergency contraception are used to prevent pregnancy after intercourse. The reasons why a woman decides to take such a step are of various kinds:
- doubts about the effectiveness and correctness of the use of used contraceptives;
- rape without contraceptive use;
- tearing or slipping of the condom during intercourse;
- displacement of the vaginal diaphragm or cervical cap;
- prolapse of the intrauterine device;
- skipping COC or delaying its reception for 3-5 hours and others.
The use of contraceptive pills after sexual intercourse is an extreme measure, they should be used only when a possible pregnancy poses a threat to the health of a woman and is accompanied by high risks of the birth of an inferior child.
Mode of application
The method of using contraceptive pills depends on the group of drugs and the dosage of the active ingredient.
Tablets with levonorgestrel are released in dosages of 0.75 mg (postinor) and 1.5 mg (escapes). You need to take them regardless of the meal no later than 72 hours after sexual intercourse. Postinor drink according to the scheme: the first tablet at once (the faster, the better) after the act, the second after 12 hours. If there is vomiting for 3 hours after taking the pill, take another one.
Escapel will keep 2 times the dosage of the active substance, so it is consumed once 1 tablet, the second pill is taken only if in response to taking the first there was vomiting.
Mifepristone is recommended for use in medical institutions under the supervision of a doctor. The dosage for medical abortion is 600 mg once. Take the tablet inside 1-1.5 h after a light meal, drink down a glass of water. To enhance the effect, sometimes an additional method of prostaglandins (misoprostol, gynoprost) is required. To assess the effectiveness of the drug after a few days, a woman is made an ultrasound of the pelvic organs and determines the level of the hormone β-hCG.
COCs to prevent unwanted pregnancies, like Postinor, should be taken within 72 hours after sexual intercourse. The regimen includes two times the use of tablets at intervals of 12 hours, regardless of food. The dosage for one dose is 100 μg of estrogen (ethinyl estradiol) and 500 μg of progestogen (desogestrel, levonorgestrel). The number of tablets is calculated for each drug individually depending on the concentration of hormones.
Important: Assigning pills for emergency contraception alone is very dangerous, since the consequences can be unpredictable. Only the doctor will be able to find the best way to solve this problem, taking into account the patient's age, health status and the term after sexual intercourse.
The negative consequences of birth control pills
Taking birth control pills after the act without the use of contraceptives is only permissible in emergency cases no more often than once a year. They are considered safer for a woman's health, have fewer complications and an easier rehabilitation period than a full-fledged surgical abortion, but their use is fraught with side effects, worsening of the general condition, and adverse long-term consequences. Contraceptive pills at a certain stage disrupt the normal physiological functioning of the female reproductive system, which in the future can lead to hormonal failure , difficulties with conceiving and bearing a child.
The serious negative consequences that usually result from the systematic or too frequent use of such birth control pills include:
- high risk of ectopic pregnancy;
- uterine bleeding;
- disorders of the cycle of menstruation ;
- bleeding in the period between menstruations;
- infertility (especially when used by young girls);
- increased propensity to thrombosis;
- increased risk of developing Crohn's disease.
After taking the tablets, the following temporary side effects are possible:
- painful sensations and swelling in the mammary glands;
- nausea, vomiting, problems with stools;
- headache, dizziness;
- a rise in body temperature, chills;
- general weakness;
- exacerbation of chronic inflammatory processes of the organs of the reproductive system;
- pain in the lower abdomen of the aching or cramping;
- allergic reactions.
Violations of the emotional state are often observed.
Contraindications
Contraceptive pills after sexual intercourse are serious medications that can harm the body. Their use is contraindicated in case of:
- allergic reactions to any of the pill components;
- severe pathologies of the liver, kidneys and bile ducts;
- unformed or unstable menstrual cycle;
- breastfeeding;
- ectopic pregnancy in anamnesis;
- propensity to thrombosis;
- adrenal insufficiency;
- violations of the process of blood coagulability.
Do not use drugs in the presence of hormone-dependent tumors and inflammatory processes in the organs of the reproductive system.
Video: Doctors of emergency contraceptive methods