Women who turn to in vitro fertilization are no longer at risk of uterine cancer. The impact on breast cancer risk is also zero. This is stated in a study based on the analysis of over 250,000 British women, led by Dr. Carrie L. Williams. According to the findings, IVF has an effective impact only on women with other risk factors.
In vitro fertilization involves repeated exposure to high levels of hormones. Over the years, doctors have wondered if this does not increase the risk of cancer. Past studies had already confirmed that the impact is inconsistent, but they were all very small. For this reason, Dr. Williams wanted to assess the risk on a larger population.
The research team studied data from over 255,768 in vitro fertilization women between 1991 and 2010. The average age of the first treatment was 34.5 years for 1.8 cycles per person. Only 20% of the participants resorted to more than 2 stimulation cycles. Scientists compared the rate of tumors within the group with the average one. They did not find any significant difference.
The average follow-up was 8.8 years and the maximum of 19 years. In this time frame, there were 164 cases of cancer against 146.9 of the general population. There was a minimal increase in breast cancer cases (191 vs. average 253.5), but it occurred mainly among those who had undergone 5 or more IVF cycles. A very rare case, therefore.
The study appears to exclude a significant correlation between tumor and IVF. Nevertheless, researchers do not rule out any negative consequences later in the years. Furthermore, it is possible that the causes of infertility are somehow linked to an increased risk of cancer.