WITHThere is concern that this assisted reproductive technology increases the likelihood of malignant diseases in women. We decided to check whether such fear is justified by scientific data.

The fact that IVF is associated with an increased risk of cancer is regularly written not only Media, but also profile resources. At the same time, various data are provided that assess both the likelihood of such consequences and the degree of risk. Thus, on the website of the Kazakhstan “Portal of information support for healthcare managers” approved: “Women of any age who become pregnant after IVF have a 10% higher chance of breast cancer,” and published on the website Oncology.ru reports about the risk of breast cancer after IVF from 10% to 31%. Websites write about a 37% increase in the risk of ovarian cancer Multidisciplinary diagnostic center in Serpukhov, Israeli clinic "Hadassah" And Moscow surgeon, urologist-oncologist Oganes Dilanyan. But these are not the most frightening numbers: news portal Tomsk.ru reports: “Women who give birth after IVF for the first time at age 40 or older have a 65% higher risk of developing breast cancer than those who conceive independently at the same age.”

In vitro fertilization (IVF) is method therapy for infertility, which gives a chance to become parents to couples experiencing difficulties conceiving. IVF involves high-tech procedures whose goal is to obtain and fertilize eggs outside the body. The IVF procedure was successful for the first time carried out in 1978 in the UK, when Louise Brown was born - the world's first test tube baby.

Modern IVF consists of of several key steps. First, the doctor conducts a complete medical examination of the couple, including tests and ultrasound, then, using hormonal drugs, stimulates the maturation of several eggs. On the 13th–15th day of the cycle, eggs are collected from the ovaries under ultrasound guidance. They are placed in a special environment with treated sperm for natural fertilization, or the ICSI method (intracytoplasmic sperm injection) is used. Fertilized eggs develop in an incubator over three to five days and become embryos. Those that have the greatest potential for implantation based on external morphological characteristics are transferred into the uterine cavity using a thin catheter. After this, the woman is prescribed hormonal drugs to support pregnancy.

The likelihood of pregnancy after an IVF procedure varies and depends on many factors: the woman’s age, the cause of infertility, the quality of the eggs and sperm. On average, the possibility of successful conception during IVF ranges from 20% to 50% per attempt, but this number can vary, and significantly. Women under 35 have a better chance, while women over 40 have less success.

The greatest concern from the point of view of increasing the risk of cancer accompanies precisely the stage of hormonal stimulation, target which is to cause hyperovulation, that is, the simultaneous maturation of several eggs in one menstrual cycle. This procedure increases the number of possible attempts to induce pregnancy. Usually only one egg matures in a natural cycle, but IVF requires more because not all eggs can be fertilized and not all embryos will develop properly.

Exists some groups hormonal drugs that doctors use to stimulate ovulation, as well as several protocols of different durations. The first group of such substances are gonadotropins, drugs containing follicle-stimulating (FSH) and luteinizing (LH) hormones. Clomiphene is usually used as a second drug; it inhibits the effect of estrogen and stimulates its own production of FSH. Finally, when the eggs are ready to be released from the follicles (usually 36–34 hours before the ovarian puncture), the woman is given an injection of human chorionic gonadotropin (hCG), which triggers ovulation.

The body itself produces FSH, LH and hCG; they do not directly provoke the growth of malignant neoplasms, but the hormones estrogen and progesterone associated with them do can participate in the development of cancer: carcinoma of the breast, ovaries, uterus and prostate. In addition, many during the IVF procedure are wary of ovarian puncture, since even a minor injury, in theory, can contribute to cell degeneration.

Although IVF is a relatively new procedure, doctors are carefully studying its safety. In 2016, a team of researchers from the Netherlands let me down results of a 23-year follow-up of 25,000 women. Some of the subjects turned to the IVF procedure due to infertility, others tried to conceive a child using other methods. Data on the incidence of breast cancer among these patients were compared with information from a national cancer registry. It turned out that this type of malignancy was equally common in the group of patients who underwent IVF (an average of 3.6 cycles per woman), and in the group of women treated for infertility by other means, and in the population as a whole.

An even larger sample turned out to be at the disposal of Greek scientists - they analyzed the medical records of 1.5 million women. Of these, almost 15,000 were diagnosed with breast cancer; only 576 of these 15,000 patients underwent IVF protocols.

At the same time, IVF Maybe even protect women from breast cancer, although not directly. Breastfeeding is associated with a reduced risk of this pathology - on average, each year of lactation reduces the likelihood of developing the disease by 4%, and in carriers of the BRCA1 mutation (determines a hereditary predisposition to breast and ovarian cancer, which is characterized by an extremely aggressive course) - by as much as 37%.

In 2018, British scientists studied A 19-year dataset of 255,786 women who used IVF. These women were less susceptible to breast cancer - 2578 cases of this pathology were recorded versus 2641.2 expected according to population statistics. Also among them there were fewer cases of invasive breast cancer (2272 versus 2371.4), but slightly more of the same cancer in situ (as stage zero, or precancer, is called, when malignant cells divide at the same rate at which they die, that is, the tumor has no potential to increase in size) - 291 versus 253.5. However, women who underwent IVF were more likely to have uterine cancer (164 vs. 146.9) and ovarian cancer (405 vs. 291.82).

However, the last set of numbers does not look so scary in absolute terms. “Ovarian cancer is not a very common tumor, in absolute terms the increase is five additional cases per 100,000 women per year,” explains oncogynecologist Pavel Sorokin. Moreover, the increased risk of ovarian tumors was mainly limited to women with endometriosis. This disease, on the one hand, often causes infertility, on the other hand, its connection has been discovered specifically with ovarian cancer. Women undergoing IVF because of their own infertility, for which doctors could not find the cause, or because of various problems on the part of the man, did not have this increased risk. Moreover, a full-term pregnancy associated with a reduced risk of ovarian cancer, so in the case of infertility due to endometriosis, pregnancy resulting from the use of assisted reproductive technology (ART) may also have a protective effect.

Having studied 40,000 women who went through IVF, Dutch scientists notedthat the technology increases the risk of ovarian cancer slightly: for women over 55 years old - from 0.2% (average risk for the population) to 0.3%. In addition, the risk does not depend on the number of IVF attempts. Scientists suggest that the risk of malignancy is increased not by the protocol itself, but by what led to it, that is, the cause of infertility. Meta-analysis A 2024 study conducted in the UK included 188 studies on the connection between ART (hormonal stimulation of the ovaries alone or together with IVF, as well as intracytoplasmic sperm injection) with oncological pathologies of the female reproductive system. The scientists also found a slightly increased risk of ovarian cancer in some studies, but they said these associations are not yet well supported or explained.

In 2019, Iranian scientists held a meta-analysis of 81 published articles examining the effect of hormone stimulation drugs on changes in the risk of various cancers. Scientists were interested in such pathologies as carcinoma of the breast, ovaries, endometrium, uterus, cervix, colon, thyroid, skin and non-Hodgkin's lymphoma. Researchers found no evidence that drugs used as part of an IVF protocol increase the risk of any of these diseases. Similar meta-analysis, conducted at the University of California (USA), also did not demonstrate an increased risk of thyroid, colon, cervical or melanoma cancer after IVF. Also No even a theoretical connection between IVF and brain tumors, since this group of pathologies is not hormone-dependent, and therefore there is not even a potential mechanism of influence.

However, there is indeed a connection between IVF and undesirable effects for both the mother and the fetus. For example, a 2024 meta-analysis as a consequence of such conception notes abnormal position of the fetus in the uterus, which can complicate the birth process or make vaginal birth impossible. Another meta-analysis demonstratesthat children conceived through ART have a higher risk of congenital urogenital malformations and malformations of the musculoskeletal system. In addition, both the IVF procedure and the circumstances caused by its necessity, there may be associated with a number of epigenetic abnormalities in the fetus. Therefore, ART should not be considered as safe as natural conception.

Thus, there is insufficient evidence to support the concern that IVF significantly increases the risk of cancer. Pregnancy itself (regardless of whether the conception was natural or occurred with the help of ART), as well as breastfeeding after it, is accompanied by a reduced risk of a number of malignant neoplasms. Some studies suggest that women who undergo IVF may have a higher risk of cancer. But scientists emphasize that, most likely, the reason lies not in the procedure itself, but in the factors that caused infertility.

Cover image: Image by Marjon Besteman from Pixabay