Clexane during early and late pregnancy: why is it prescribed?

, medical expert
Last reviewed: 11.04.2020

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What you need to know about the use of the drug Clexane during pregnancy? In the period of childbearing, the expectant mother can face a variety of health problems that she did not know about before pregnancy. Thus, a blood test sometimes indicates that a woman has too thick blood: this problem can greatly harm both the course of pregnancy and the developing baby, and the risk of thrombosis, heart attacks and strokes in the female body sharply increases.

Is introduction of clexane safe? Who needs this drug, and who can do without it?

Clexane when planning pregnancy

Even at the planning stage of pregnancy, a woman is recommended to analyze blood for the quality of blood coagulation - to do a so-called hemostasis test. Based on its results, it is possible to prevent the development of complications, and a woman will be able to conceive and carry out a child to the proper term.

Mandatory coagulogram assigned:

  • women in the family who had cases of heart attacks, strokes, thrombosis, varicose veins (or if the woman herself has such a problem);
  • if the patient already had a failed pregnancy that ended in miscarriage or fetal frost;
  • if a woman is actively involved in sports, or has problems with the digestive, endocrine system, metabolism.

If the potential future mother does not belong to any of the risk groups, then the doctor can still send her for an analysis - at her discretion. Before the procedures of assisted reproductive technologies (IVF, ICSI, IISM), the quality of blood clotting is studied in any case.

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Is Clexane possible during pregnancy?

The formation of blood clots is a great danger during pregnancy. One of the most common risks is blockage of blood vessels through which blood moves. This pathology can be a problem not only for the growing fetus, which can develop oxygen starvation, but also for the expectant mother. In such a situation, the probability of spontaneous abortion, fading of pregnancy, as well as infarction and stroke conditions significantly increases. Pregnancy freezing is due to impaired endometrial blood circulation, and the nutrient supply of the fetus suffers. In addition, because of such a violation, the embryo becomes difficult to consolidate.

To avoid these problems, the doctor may prescribe Clexane to pregnant women: many patients only thanks to this drug are carrying the baby without complications. However, Clexane during pregnancy is not prescribed "just because": this requires the presence of appropriate indications.

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Indications Clexana during pregnancy

Not in all cases it is possible to solve the problem of excessively thick blood by correcting nutrition and lifestyle. When condensation is a threat to the fetus or future mother, the doctor will hasten to prescribe medications, taking into account the indicators of the coagulogram and the state of the pregnant.

In general, Clexane is used to prevent the development of hypercoagulation syndrome. In the period of gestation in the female body, physiological enhancement of blood coagulation is observed. This happens in the most natural way: nature has provided in order to minimize blood loss during labor.

If such a physiological phenomenon during pregnancy does not exceed the limits of the norm, then Clexane's administration will not be required. After the baby is born, the woman's hemostasis system returns to normal levels that were before pregnancy. The situation is different if coagulation disorders go beyond the established limits. In such a situation, it is necessary to prescribe medications to thin the blood and reduce the likelihood of thrombus formation. It is here that Clexane, or similar in action, representatives of low molecular weight heparins is needed.

A specific indication for the use of Clexan during pregnancy is thrombophilia - a disease that is accompanied by increased thrombosis in the vessels (more in the veins). Often, thrombophilia is diagnosed in the process of gestation, when the third placental circle of blood circulation is formed in the female body. The patient increases the degree of clotting, thrombi form in the vascular lumen, which overlap the placental-uterine and placental-fetal network. Blocks interfere with the normal blood supply to the fetus, which begins to experience a lack of oxygen and nutrients. Clexane with thrombophilia helps to "break" blood clots in a timely manner and prevent their formation.

Pathologies such as uterine hematomas require special observation by a doctor. Their formation can be associated with severe toxemia, high blood pressure, injuries and exercise, as well as hemophilia, thrombophilia, metabolic disorders. The appearance of a hematoma may affect the development of the embryo. In addition, premature placental abruption can begin. The purpose of the drug Clexan in hematoma in the uterus during pregnancy contributes to blood thinning, improves the quality of nutrition of the fetus, prevents hypoxia.

The benefits of Clexane for fetal development in many cases are beyond doubt. Therefore, many future mothers are interested: does it make sense to introduce Clexane for prophylaxis during pregnancy? Indeed, some gynecologists are in a hurry to prescribe the drug even at the slightest doubt, even in the case when the hemostasis of a woman is within the normal range. However, most doctors are unanimous: Clexane should be used only if it is clearly necessary. If such a need is “illusory,” then it is better to pay attention to other, more benign ways to optimize the quality of blood clotting.

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Release form

Clexane is a direct acting anticoagulant. It is produced in the form of a solution for subcutaneous administration, which is packaged directly in syringes of different volumes. A cardboard box contains five blister plates for a pair of syringe-doses in each plate. One syringe dose has a needle with a special protective system. The solution is clear, without color, or with a slightly yellowish tinge.

Enoxaparin is the active ingredient. In one milliliter of solution, there are 10 thousand anti-Xa IU, which is equivalent to 100 mg of enoxaparin sodium.

Clexane 0,2, 0,4, 0,6, 0,8 and 1 ml contains the active component 20, 40, 60, 80 and 100 mg, respectively.

As an auxiliary component is water for injection.



The active ingredient of Clexane belongs to low molecular weight heparins, with independent antithrombotic and anticoagulant activity. Clexane has a high ratio of anti-Xa to anti-IIa activity. This ratio is equal to 3.6. Clexane has the following positive properties:

  • reduces the activity of coagulation factor IIa;
  • increases bioavailability;
  • possesses predictable anticoagulant capacity;
  • improves glomerular filtration;
  • accompanied by a low frequency of antibody production;
  • osteoblasts are not significantly activated.

Clexane is effective when given subcutaneously, has a long half-life. The therapeutic effect occurs on the background of the introduction of the drug once a day. Treatment with Clexane is characterized by a low incidence of thrombocytopenia and osteoporosis.

Today, medical professionals do not have reliable information that the active component of Clexane during pregnancy overcomes the placental membrane. Unfortunately, the necessary research for this has not yet been conducted. Experiments on animals do not always fully reflect the true picture that occurs in the human body.

However, in clinical practice, not a single case has been registered where any negative consequences would develop for a child if his mother was pricked with Clexan during pregnancy. The main points: the medication should be prescribed strictly according to indications, in the lowest possible dosage, with constant monitoring of the quality of blood clotting.

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After subcutaneous injection, the active component of Clexane is fully absorbed (almost completely). The maximum possible degree of activity in serum is noted after 3.5 hours. A steady concentration is determined already on the second day from the start of treatment.

Within the limits of the recommended dosing, Clexan’s kinetic properties are linear. Concentration of the drug is predictable and is within the therapeutic interval.

The distribution of anti-Xa activity is close to 5 liters (almost the volume of human blood).

The half-life of anti-Xa activity is longer than that of unfractionated heparins. Monophasic withdrawal, with a half-life of about 4 hours after a single subcutaneous injection, and about 7 hours after repeated injections.

The active component and metabolites are excreted through the kidneys and the hepatobiliary system. The renal clearance of elements with anti-Xa activity may be about 10% of the amount of drug administered. The total excretion by the kidneys is 40% of the dose.

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The doctor will not prescribe Clexane during pregnancy in the following cases:

  • if there is a threat of spontaneous abortion against the background of an increased risk of bleeding;
  • with diagnosed vascular and aortic aneurysms;
  • if the patient suffered a stroke (ischemic or hemorrhagic form);
  • if the patient has hypertension;
  • in severe diabetes;
  • with a lack of renal function;
  • with liver failure;
  • if the woman has artificial heart valves.

The introduction of Clexane after 36 weeks of gestation is not recommended, but this issue is resolved individually: in some cases, the drug can be used right up to delivery and even for some time after the birth of the baby.


Side effects Clexana during pregnancy

Bleeding of varying degrees is considered the most frequent and dangerous adverse event during treatment with Clexane. That is, even if a woman notes in her small bleeding during pregnancy, arising during treatment, it is necessary to stop the introduction of the drug and immediately consult a doctor.

More pronounced bleeding from Clexane during pregnancy is possible with an incorrectly chosen dosage, in the absence of control over the state of the blood coagulation system, with the administration of the drug without adequate indications.

In isolated cases, hemorrhagic syndrome was observed, with intracranial and retroperitoneal hemorrhages. The use of Clexane with simultaneous epidural anesthesia can lead to the formation of a hematoma in the space of the spinal cord.

Freezing pregnancy on Clexane is not a consequence of treatment with this drug, and may indicate only the presence of other factors that could lead to complications.

Allergy to Clexan during pregnancy is more often manifested by local symptoms:

  • pain in the area of administration of the drug;
  • swelling, redness;
  • bruising, compaction.

In some cases, systemic reactions can also be detected (up to the inflammatory process in the vascular walls).

Side effects such as thrombocytopenia or increased transaminase, have no particular clinical significance and are always temporary.

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Dosing and administration

The drug Clexane is produced in different volumes, because the doctor sets the dosage individually, depending on the results of the patient's tests. Most often, injections of the drug are performed at a dose of 40 mg daily, once a day, for 2 weeks or more.

With the pathology of deep venous vessels, the dosage of Clexane is made during pregnancy by weight: the amount of the drug is calculated from the ratio of 1.5 mg / kg of the woman’s weight.

A common question: where can you prick Clexane during pregnancy? Injections are performed subcutaneously, in the abdominal region, namely, in the right or left segment, not less than five centimeters from the umbilical point. Injections are produced alternately, then in the right, then in the left segment.

There should be no doubt where to prick Clexane in late pregnancy. The drug is administered exclusively in the abdominal area, while respecting all the necessary conditions and rules.

Pre-carefully study the instructions on how to prick Clexane in the stomach during pregnancy:

  1. Wash your hands with soap or treat with a disinfectant. The patient lies down on a bed or a couch.
  2. Presumably schedule an area for the injection.
  3. Treat the intended injection with a cotton pad moistened with alcohol.
  4. Carefully remove the cap from the needle connected to the syringe filled with the drug Clexane. The syringe is completely ready for use. Do not pre-press on the piston protrusion to remove air bubbles, as this may disturb the dosage of the drug. The needle is sterile and should not touch anything until the complete injection of the solution.
  5. The skin on the stomach is taken in a thick fold with the help of the index and thumb of the free hand. Important: the fold should be kept during the entire period of administration of the drug.
  6. The syringe is held so that the needle is directed downwards (vertically) and has been inserted into the fold for the entire length.
  7. With a thumb press the piston protrusion, inject the drug, and with the other hand hold the fold.
  8. Remove the needle from the skin without changing the angle of inclination. The skin fold is released.
  9. The syringe with the needle is directed downwards and away from itself, pressing the piston protrusion all the way down: this action should activate the installation of a protective cover. Next, the syringe should be thrown away.

The injection site should not be rubbed, kneaded, lubricated with creams and gels.

The usual frequency of administration of the drug - daily, once a day. Intermittent injections of Clexane every other day during pregnancy are undesirable, as this violates the persistent state of hemostasis.

  • Clexane in the first trimester of pregnancy is undesirable to prescribe in order to prevent or treat blood clots. This clinical information, which is available to specialists, is not enough to determine the likelihood of adverse effects of the drug on the fetus or during pregnancy itself. If the doctor prescribes Clexane during early pregnancy, then he must carefully weigh all the risks, resorting to the help of the medication only in case of real need.
  • Clexane in the 2nd trimester of pregnancy can be prescribed for therapeutic purposes, since there is a clinical possibility of using the drug without teratogenic or fetotoxic effects. However, additional research before using Clexane is mandatory: the drug is prescribed only if other means of a similar effect fail.
  • Clexane in the 3 rd trimester of pregnancy can be prescribed if blood clotting indicators indicate the need for such a step. In most cases, the drug is used up to 36 weeks, but for individual patients, treatment can be continued, at the discretion of the physician.

Do not be afraid to use Clexane in late pregnancy, if the doctor insists on it. If necessary, the drug is administered until the day of birth, possibly canceling it 12 hours before the onset of labor.

It is advisable to perform the injections daily at the same time, with an allowable range of ± 1 hour.

What to do if Clexana missed an injection during pregnancy? Skipping a single injection should not adversely affect the state of hemostasis, however, the following injections should be done on time and regularly.

How much to prick and how to cancel Clexane during pregnancy, the doctor decides. In some cases, the drug is abolished abruptly, in others it is gradually replaced by another drug. This question is solved individually, because everything depends on the blood parameters and the state of the patient’s coagulation system.

It is also possible temporary cancellation of Clexane during pregnancy, if the doctor sees this as a necessity. Such cancellation should be monitored by a hematologist and accompanied by appropriate blood tests.


Accidental over-administration of Clexane can cause dangerous hemorrhagic complications. That is why drug treatment is always carefully monitored by a hematologist.

If an overdose does occur, a kind of Clexan antidote is often used - it is about protamine sulfate: to neutralize 1 mg of Clexane, the same amount of protamine should be given to the doctor. If more than eight hours have passed since the last injection of Clexane, the dosage of the antidote can be reduced: 0.5 mg of protamine per 1 mg of Clexane will be required. If the last injection of Clexane occurred more than twelve hours ago, then the use of antidote is no longer necessary.

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Interactions with other drugs

Experts note that some combinations of drugs with Clexane can bring about the development of hyperkalemia. Among these drugs are potassium salts, potassium-saving diuretics, angiotensin-converting enzyme inhibitors or angiotensin II receptors, nonsteroidal anti-inflammatory and heparin-containing drugs, as well as Trimethoprim, Cyclosporine and Tacrolimus.

Hyperkalemia develops not in all patients, but only in those who take these medicines at the same time.

During pregnancy, Clexane and Curantil are often prescribed together: against the background of blood thinning, growth and development of the fetus, which receives more nutrients and oxygen, improves. However, such combined treatment must necessarily and be regularly monitored by a hematologist.

Do not combine Clexane with preparations inhibiting fiblinolysis. For example, the simultaneous reception of Tranexam and Clexane, as a rule, is inappropriate.

Clexane during pregnancy goes well with angioprotectors and capillary stabilizing drugs. You can often find a combination like Phlebodia 600 and Clexane: during pregnancy, this combination allows you to increase the capillary tone, improve venous outflow and lymphatic drainage.

Aspirin paired with Clexane significantly increases the risk of bleeding: platelet function is inhibited, the digestive system is affected. In addition, taking acetylsalicylic acid during pregnancy is generally contraindicated: if it is necessary to achieve the antipyretic effect, it is preferable to use Paracetamol (Panadol, etc.).

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Storage conditions

The syringe dose is stored in the original packaging and box, in places protected from direct sunlight and access of children. The optimum storage temperature is up to 24-25 ° C. The drug should not be subjected to freezing and heating.


Shelf life

Packaging with Clexane retain up to 3 years from the date of issue. The opened syringe should be used immediately: it cannot be stored.

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Clexane is a fairly expensive medication. However, you should not look for analogues, based on the issues of economy: other drugs, representing a group of low molecular weight heparins, have a weaker effect, which may not be enough to ensure adequate blood clotting.

If the coagulogram indices are slightly outside the normal range, then the initial use of analogs is not excluded. Clexane is prescribed only when similar means do not justify themselves and do not have the desired effect. What kind of analogs are we talking about:

  • Fraxiparin is a drug based on nadroparin calcium, has antithrombotic activity and is often used during the preparation for pregnancy.
  • Hemapaksan, Novoparin, Flenox, Eclexia are drugs based on enoxaparin, so they can be called complete analogs of Clexan. However, the doctor must approve the replacement of such medicines, since there are many nuances and risks that arise only during the clinical application of these drugs.
  • Fragmin is a drug represented by the active ingredient dalteparin. It can be used in the form of subcutaneous and intravenous fluids.

trusted-source[28], [29], [30], [31], [32]

Doctors reviews

If the doctor considers it expedient to prescribe Clexane during pregnancy, then it is hardly worth discussing this prescription - this is especially true for cases where tests indicate a tendency to form blood clots. The drug treatment is carried out only under constant medical supervision, in compliance with all the subtleties of the introduction and dosage of the solution.

Despite possible side effects, the benefits of Clexane are more than noticeable: this medication is irreplaceable if we are talking about the threat of carrying a fetus, or about violations of its development, which is associated with pathological thickening of the blood.

During treatment, a woman should be required to take a blood test regularly and regularly to control the quality of clotting. Such measures are necessary because, based on the results, the doctor can draw conclusions about the effectiveness of Clexan in pregnancy, as well as trace the possibility of complications and assess the likelihood of risks.

trusted-source[33], [34]


To simplify the perception of information, this instruction for use of the drug "Clexane during early and late pregnancy: why is it prescribed?" translated and presented in a special form on the basis of the official instructions for medical use of the drug. Before use read the annotation that came directly to medicines.

Description provided for informational purposes and is not a guide to self-healing. The need for this drug, the purpose of the treatment regimen, methods and dose of the drug is determined solely by the attending physician. Self-medication is dangerous for your health.

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