A new study finds no association between in vitro fertilization (IVF) and a woman's increased breast cancer risk. The new findings debunk the previously assumed link between the fertility treatment and the disease and offer peace of mind to many women.
For the study, the research team from the Netherlands Cancer Institute in Amsterdam, analyzed the data of over 25,000 women. The data were collected between the years 1980 and 1995.
The study participants involved both women who underwent IVF (19,158) and women who didn't get the treatment (5,950). The average age of the women in the IVF group was 54 years old and 55 years old in the non-IVF group.
The analysis found no difference in the breast cancer rates of women who had IVF and those who did not undergo the said treatment.
Within the 21-year followup, 839 women were diagnosed with breast cancer. There were also 109 women who received diagnoses of non-invasive breast cancer. The main finding is that the breast cancer rates of the women in both groups show no significant difference.
Breast cancer's first manifestations were documented 20 years after the IVF treatment among participants. The researchers found that women who had modest IVF treatment results had lower risks of developing the disease.
"The cumulative incidences of breast cancer at age 55 were 3 percent for the IVF group and 2.9 percent for the non-IVF group," concluded the team," the researchers concluded. The new findings were published in The Journal of the American Medical Association (JAMA) on July 19.
During an IVF treatment, doctors remove eggs from the woman's ovaries. These are then combined with a sperm in a lab setting and surgically placed back into the woman's body. According to the U.S. Centers for Disease Control and Prevention (CDC), there were 67,996 IVF-born American children in 2013 alone.
IVF was previously thought to increase women's breast cancer risks and doctors agreed that the disease could be linked to the high exposures to progestogens as well as endogenous and exogenous estrogens.
According to the new study, while IVF reduces the progesterone levels temporarily, the procedure doesn't result in a surge of breast cancer incidence among the women who had it.
"The main takeaway is there's no evidence of an increased subsequent risk of breast cancer, at least in the first couple decades," said oncologist Dr. Saundra S. Buys from University of Utah's Huntsman Cancer Institute. Buys was not part of the study.
Photo: Raúl Hernández González | Flickr