A large nationwide study from Finland has found no evidence that prior abortion or miscarriage increases the risk of developing breast cancer, either before or after menopause.

The findings were published in Acta Obstetricia et Gynecologica Scandinavica and are based on high-quality national registry data. According to the research, neither induced abortion nor miscarriage was associated with an increased risk of premenopausal or postmenopausal breast cancer.

The nationwide registry-based study analyzed data from 31,687 women diagnosed with breast cancer between 1972 and 2021 and compared them with 158,433 women without breast cancer. Researchers found that the risk of breast cancer was similar among women with a history of induced abortion and those with no history of abortion, both before and after the age of 50. The same was true for women who had experienced miscarriages.

Importantly, the study also found no significant differences in breast cancer risk depending on the number of abortions or miscarriages, or the age at which the first abortion or miscarriage occurred.

“Miscarriage or induced abortion as potential risk factors for breast cancer has continued to raise concerns and has led to the spread of misinformation. In this study using high-quality Finnish registry data, we can reliably eliminate these concerns. Induced abortion or miscarriage are not risk factors for breast cancer, even if there are several of them. This information is important and reassuring for millions of women around the world,” said Oskari Heikinheimo, MD, PhD, corresponding author from the University of Helsinki and Helsinki University Hospital.

The findings provide strong reassurance for women and contribute to evidence-based discussions on reproductive health.

Source: News Medical
Study: Acta Obstetricia et Gynecologica Scandinavica