Medicinal Products

Questions and Answers on Combined Contraceptives

Why is new information available now?

A comprehensive review of the benefits/risk ratio of the use of combined oral contraceptives has been carried out in the EU, focusing especially on the risk of blood clots forming associated with the use of these medicines.

In this way, HALMED wants to provide more information on the risk of blood clot forming associated with the use of combined hormonal contraceptives, including the information on conditions that increase the risk from blood clots, information and signs and symptoms of blood clots and information when to tell the doctor or pharmacist about the use of these medicines.

Taking account that the recent benefits/risks review relates directly to the blood clots forming, HALMED is publishing a number of information regarding exactly this risk. However, it is important to bear in mind that combined hormonal contraceptives are very effective in preventing unwanted pregnancies and that the overall risk of blood clots is small. For the majority of women, the benefits of these medicines continue to outweigh the risks of serious adverse reactions.

These data are not about the medicines containing only progestogen and not containing ethinylestradiol or estradiol.

What are the conclusions and recommendations of the review?

The risk of blood clots associated with the use of combined hormonal contraceptives has been well-known for years and doctors and patients are familiar with a large number of information on this issue. The recent review has confirmed the previous findings that the risk is small and therefore the providing of useful information is now emphasized.

If you have been taking combined hormonal contraceptives without any problem, there is no reason for you to stop taking them on the basis of this review. In the case of worry, you should talk to the prescribing doctor at the next routine appointment, but in the meantime, continue to use the medicine. It is important to bear in mind that a sudden interruption in taking combined hormonal contraceptives may result with an unwanted pregnancy.

What are combined hormonal contraceptives?

Combined hormonal contraceptives are medicines very commonly used for preventing unwanted pregnancy. These medicines contain two types of hormones, an oestrogen and a progestogen. Oestrogen contained in the majority of medicines is ethinylestradiol, but some medicines contain other oestrogen which is estradiol. There is a number of progestogens available.

What are the benefits of taking combined hormonal contraceptives?

In addition to preventing from unwanted pregnancy, combined hormonal contraceptives have also other long term advantages, such as decreasing the risk of endometrium (inner uterus layer) cancer and ovary cancer.

Combined hormonal contraceptives sometimes may have other benefits, such as better menstrual cycle control, improvement of endometrioses symptoms (inner uterus layer disorder), inflammatory pelvis disease and in some women acne. The comparative benefits of different combined hormonal contraceptives have been studied only in a few trials and therefore it is not known whether significant differences among them exist.

For the majority of women, the benefits of these medicine largely outweigh the risks of serious adverse reactions.

What are the risks from combined hormonal contraceptives?

Like all other medicines, combined hormonal contraceptives are associated with some of the risks. The most common risks include breast tenderness, mood swings, change in body mass. Large studies have also discovered very small risks from breast cancer and cervical cancer.

Blood clots are most probably the most important risks associated with these medicines.

What may happen if I have a blood clot?

Blood clots initially form in the legs (which is called deep venous thrombosis), but in some cases they may detach and be transported into blood vessels in the lung (which is called pulmonary embolism). Blood clots may also be formed in blood vessels of the heart, which causes heart attack, or in blood vessels of the brain, which causes stroke. Blood clots, therefore, may be a very serious adverse reaction, leading, however, in rare cases to a fatal outcome.

How high is the risk of blood clots with combined hormonal contraceptives?

All combined hormonal contraceptives slightly increase the risk of blood clots, however, it is important to bear in mind that this risk is small.

The risk of blood clots forming is the highest within the first year of use of combined hormonal contraceptives - this relates to patients that have never before been using these medicines, as well as patients with an interruption of use of these medicines for 4 weeks or more. The risk of blood clot forming is higher in those patients having other risks factors (see part "What other factors may increase the risk of blood clots?")

The risk for blood clots forming associated with combined hormonal contraceptives decreases after the first year of use, but remains higher than in women not taking these medicines. The risk returns to the normal level after stopping the use of these medicines.

Is the blood clot risk the same with all combined hormonal contraceptives?

Large studies carried out over the years have provided good evidence that the blood clot risk may vary among different combined hormonal contraceptives. It is considered that the difference depends on the oestrogen dose and progestogen type contained in these medicines. It is important to emphasize that the overall risk of blood clots associated with the use of any of these medicines is lower for the majority of patients.

Ethinylestradiol-containing hormonal contraceptives combined with one of the following progestogens: levonorgestrel, norgestimate or norethisterone have lower risk as compared to medicines from this group containing other progestogens.

How many women will have a blood clot?

It is considered that:

  • Approximately 2 out of 10 000 healthy women not using combined hormonal contraceptives will in one year have a blood clot.

For comparison:

  • Approximately 5 - 7 out of 10 000 healthy patients using etinylestradiol and levonorgestrel, norgestimate or norethisterone - containing combined hormonal contraceptives will in one year have a blood clot.
  • Approximately 9 - 12 out of 10 000 healthy patients using ethinylestradiol and gestodene, desogestrel or drospirenone-containing combined hormonal contraceptives will in one year have a blood clot.
  • Approximately 6 - 12 out of 10 000 healthy patients using ethinylestradiol and getonogestrel, or norelgestromin-containing combined hormonal contraceptives will in one year have a blood clot.
  • The number of patients having a blood clot have yet to be discovered for some of the combined hormonal contraceptives. This includes the following combinations: ethinylestradiol and dienogest, ethinylestradiol and chlormadinone, estradiol and dienogest and estradiol and nomegestrol.
Scenario Risk for blood clot forming in one year
Women not using combined hormonal contraceptives (tablets, transdermal patch or intra-vaginal ring) and is not pregnant Approximately 2 cases out of 10 000 healthy women
Patient uses an ethinylestradiol and levonorgestrel, norgestimate or noretisterone-containing combined hormonal contraceptive Approximately 5 - 7 cases out of 10 000 healthy women
Patient uses an ethinylestradiol and gestodene, desogestrel or drospirenone-containing combined hormonal contraceptive Approximately 9 - 12 cases out of 10 000 healthy women
Patient uses an ethinylestradiol and gestodene, desogestrel or drospirenone-containing combined hormonal contraceptive Approximately 6 - 12 cases out of 10 000 healthy women
Patient uses a combined hormonal contraceptivewith one of the following combinations: ethinylestradiol and dienogest, ethinylestradiol and chlormadinone, estradiol and dienogest and estradiol and nomegestrol The number of patients that might have a blood clot has yet to be discovered

What other factors may increase the risk of blood clots?

The risk of blood clots differ among certain individuals even without using the combined hormonal contraceptives. A number of factors increases the risk of blood clots in the following cases:

  • you are older than 35,
  • you are obese,
  • you have a brother, sister or parent having had a blood clot at the relatively earlier age (i.e. younger than 50 years),
  • you have a condition that favours the risk of blood clots, like cancer.

Women who are smokers have an increased risk of blood clots causing heart attack and stroke, especially if they're older than 35.

In women not having any of the factors indicated above, the risk of blood clots forming with combined hormonal contraceptives is very low.

In women having several of the above factors, the risk of blood clot forming with combined hormonal contraceptives is higher in certain cases, the presence of several risk factors may signify that combined hormonal contraceptives should not be used and that a doctor should be consulted about the alternative contraception.

It is important to bear in mind that blood clot risk changes over time, i.e. in case of significant gaining of body weight, beginning to smoke or increasing the number of cigarettes and after surgery it is important to inform the prescribing doctor.

The attention should be paid to

It is important to pay the attention to blood clots symptoms, especially if you:

  • recently had surgery
  • have been at rest (i.e. due to an injury or illness) or have been on a longer trip)

Seek immediately doctor's advice if you have had some of the following symptoms:

Have you got any of these symptoms? What do these signs indicate?
Heavy pain or leg swelling that may be accompanied by hypersensitivity, heat or skin colour change, like paleness, redness or blue skin colour Deep venous thrombosis
Sudden unexplainable gasp or accelerated breathing, strong pain in the chest that may be intensified at deep breathing, sudden cough without apparent reason, sometimes with blood in cough up Pulmonary embolism
Pain, discomfort, pressure or weight in the chest, discomfort or pain in upper body parts spreading towards the back, jaws, throat or hands, accompanied by a sensation of stomach saturation, gastrointestinal disorders or suffocation, sweating, nausea, vomiting and lightheadedness Heart attack
Weakness or stupor face, hands or legs, in one body part in particular, hard speech or speech understanding, sudden confusion, sudden loss of seeing or lightheaded seeing, strong headaches and migraines stronger than usual Stroke

What to expect from the doctor?

You should discuss the benefits and risks with your prescribing doctor. The doctor will highlight the risk of blood clots of these medicines, conditions that increase the risk of blood clots and will go through the key signs and symptoms that patients should be aware of.

What to do if you are taking a combined hormonal contraceptive?

If you are taking a combined hormonal contraceptive without any problem there is no need, based on the completed review, to stop taking it. In the case of worry, the prescribing doctor should be consulted at the next routine appointment and keep using the medicine in the meantime.

A sudden interruption in taking combined hormonal contraceptive may result with an unwanted pregnancy. The risk of blood clots during pregnancy and immediately after birth is higher from the risk associated with the use of these medicines.

It is important keep in mind to tell your doctor (i.e. if you are will have surgery) that you are taking combined hormonal contraceptives.

Where to find further information?

If you are using a combined hormonal contraceptive, you should carefully read the package leaflet in order to be sure that you aware of the blood clot risks, informed about the signs and symptoms of blood clots (which means deep venous thrombosis, pulmonary embolism, heart attack or stroke) and that you know what to do if you think you have some of the above.

For further information it is important to seek advice from your prescribing doctor.

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