Early Childbearing Lowers Breast Cancer Risk

A recent study suggests that women who give birth in their early twenties may be at a decreased risk for developing breast cancer, according to researchers from the Harvard Stem Cell Institute. They are currently in the process of testing p27, a mammary gland progenitor marker in the tissue of women that has been collected over a 20-year period.

According to the Institute's Kornelia Polyak, MD, Ph.D., she and colleagues worked to see if this was seen as an accurate breast cancer predictor in a large population of women. They looked at the relative number of proliferative mammary gland milk-producing cells in women that could develop into cancer over time.

Through comparing the cancerous tissue to other non-cancerous cells, scientists found that women were at a higher risk for breast cancer, including those who had inherited the gene mutation BRCA1 or BRCA2, if they carried a child later in life. Yet, women who gave birth earlier in life but still developed breast cancer later had a higher number of protective mammary gland progenitors.

 "The reason we are excited about this research is that we can use a progenitor cell census to determine who's at particularly high risk for breast cancer," said Polyak, a Harvard Stem Cell Institute Principal Faculty member and Harvard Medical School professor at the Dana-Farber Cancer Institute, via a press release. "We could use this strategy to decrease cancer risk because we know what regulates the proliferation of these cells and we could deplete them from the breast."

Results showed that both obesity and women postponing having a child are both risk factors for breast cancer. The study concludes that researchers hope to develop a protective treatment that could mimic the positive effects of early child bearing.

 "In general people who study cancer always want to focus on treating the cancer but in reality, preventing cancer can have the biggest impact on cancer-associated morbidity and mortality," Polyak said, via the release. "I think the mentality has to change because breast cancer affects so many women, and even though many of them are not dying of breast cancer, there's a significant personal and societal burden."

More information regarding the study can be found in the journal Cell Stem Cell.