Hormonal contraception

A significant proportion of women of childbearing age abandon the choice of hormonal contraception in favour of other methods of preventing pregnancy because of concerns that it may cause an increased risk of cancer as a result of its use. Hormonal contraception methods currently available in Poland include:

• preparations containing one or two hormones in the form of oral pills, injections or patches.
• also available is the intrauterine hormonal system, which is a combination of a traditional IUD with a system releasing synthetic progesterone - levonorgestrel.

One of the components of most hormonal contraceptives is oestrogen hormones. It should be mentioned that they are included in the list of carcinogens compiled by the Ministry of Health. Oral contraceptives used in sequential therapy, as well as oral combined contraceptives, are listed in the appendix of this study. In view of the above, preparations containing a combination of estrogens and gestagens are the most controversial.

Correlations between the use of hormonal contraception and the induction of the most common cancers of the reproductive organs, as well as tumours occurring outside the reproductive organs, have been studied for many years and are still ongoing. Due to the fact that hormonal contraception has gained popularity relatively recently, data on this subject are still scarce. This is mainly due to the fact that there is a small group of older women using hormonal contraception in their reproductive years. Most scientific reports concern the relationship between the longest available, oral hormonal contraception and cancer.

The process of carcinogenesis

There is no doubt that the process of carcinogenesis is a very complex process that can be influenced by a huge number of factors. It is not insignificant that it can take more than 30 years from first exposure to a potentially carcinogenic agent for a cancer to manifest itself. It is well known that any interference with hormones disrupts the body's very complex hormonal regulation system. Unfortunately, it has not yet been possible to invent exogenous hormones that are completely indifferent to health.

The difficulty in drawing clear conclusions as to whether or not hormonal contraception significantly increases the risk of developing a particular type of cancer is primarily due to the introduction of ever newer hormonal preparations onto the market. Their prospective studies are not able to include a sufficient number of women and an adequate follow-up time for the results obtained to be fully sufficient to confirm the hypotheses of a link between hormonal contraception and cancer formation. All available results from studies conducted to date are inconclusive.

It has been hypothesised that long-term use of hormonal contraception, lasting 10 years or more, may increase the risk of cancer, especially breast cancer and cervical cancer. The risk increases if contraception is started before the age of 25 and before the first pregnancy. However, not all synthetic hormones have a unidirectional effect. A beneficial effect of the two-component contraceptive pill has been observed, for example, on non-cancerous conditions of the mammary gland. Women using hormones have a lower incidence of endometrial and ovarian cancer. Hormonal contraception, probably by reducing bile acid production, is also thought to reduce the risk of cancer of the colon, colon and rectum.