Late Motherhood Linked to Increased Risk of Postpartum Breast Cancer

Research indicates that having a first child after the age of 30 significantly increases a woman’s risk of developing breast cancer. A study led by Weston Porter, a professor of comparative oncology at Texas A&M University, reveals that women who give birth for the first time at this age face a 40 per cent to 45 per cent higher risk of breast cancer compared to those who have children earlier.

This specific type of cancer, known as postpartum breast cancer, typically affects women under the age of 45 within a few years following childbirth. It is often more aggressive than other forms of breast cancer, which underscores the importance of early detection and specialized treatment. According to statistics, approximately one in eleven women in the European Union and one in seven women in the United Kingdom are diagnosed with breast cancer. In 2022, around 2.3 million women worldwide received a breast cancer diagnosis, leading to 670,000 fatalities. These figures are expected to rise in the coming decades, as reported by the World Health Organization‘s cancer research agency.

Understanding the Risks

While the majority of breast cancer cases and deaths occur in women over the age of 45, about 3.9 per cent of breast cancer deaths in the EU are among women under 45. Symptoms of breast cancer can vary, including lumps, changes in breast shape or skin texture, nipple discharge, and persistent pain, though early stages may not exhibit any symptoms.

Porter’s research delves into the biological mechanisms linking pregnancy to increased breast cancer risk. His team discovered that when women have their first pregnancy in their 30s, there is a notable change in immune cell activity within the breast tissue. As Porter explained, “there is a change in the immune infiltration or inflammation that is occurring.” This corresponds with the processes of lactation and involution—when a child stops nursing—resulting in an influx of inflammatory cells, which has been associated with a heightened risk of breast cancer.

By investigating these changes, researchers aim to identify potential markers for early detection and treatment improvement. Interestingly, other studies suggest that pregnancy and childbirth can reduce breast cancer risk among older women. The new findings indicate that for first-time mothers in their 30s, risks increase in the immediate years following pregnancy but may decline over the long term.

The Impact of Childbirth Practices

The number of children a woman has and whether she breastfeeds can also influence her cancer risk. A meta-analysis conducted in 2020, which included over 50,000 women across 47 studies, found that each additional year of breastfeeding per child could reduce the risk of breast cancer by more than 50 per cent, from 6.3 to 2.7 cases per 100 women.

Given the elevated risks for women who become mothers in their 30s, Porter advises increased vigilance. He recommends that these women undergo regular mammograms and perform self-examinations to detect any lumps or abnormalities. As awareness grows regarding the implications of late motherhood, proactive health measures become essential in mitigating the associated risks of postpartum breast cancer.