Later Parenthood Increases Breast Cancer Risk for New Mothers

Research has revealed a concerning link between the age at which women have their first child and the risk of developing breast cancer. A study led by Weston Porter, a comparative oncology professor at Texas A&M University, indicates that women who give birth for the first time after the age of 30 face an increased risk of breast cancer by as much as 40 per cent to 45 per cent. This condition, referred to as postpartum breast cancer, typically affects women under the age of 45 within a few years following childbirth.

Postpartum breast cancers tend to exhibit more aggressive characteristics than other types of breast cancer, necessitating early detection and specialized treatment. According to the World Health Organization’s cancer research agency, approximately one in eleven women in the European Union and one in seven women in the United Kingdom are impacted by breast cancer. In 2022, an estimated 2.3 million women worldwide were diagnosed with breast cancer, resulting in 670,000 deaths, with projections indicating an increase in these figures over the coming decades.

Understanding the Risks and Symptoms

While the majority of breast cancer cases and related fatalities occur in women over the age of 45, around 3.9 per cent of breast cancer deaths in the European Union occur among women under 45. Symptoms of breast cancer can include lumps in the breast, changes in breast shape or skin texture, nipple discharge, or persistent pain. Early stages of the disease, however, may present no symptoms at all.

Porter’s research delves into the biological mechanisms linking pregnancy and breast cancer risk. His findings suggest that the age at which a woman experiences her first pregnancy significantly influences her breast cancer risk. Specifically, when women have their first child in their 30s, there is a notable change in immune response within the breast tissue. Porter explains, “There is a change in the immune infiltration or inflammation that is occurring in the breast,” particularly during lactation and the subsequent involution phase when breastfeeding ceases. This increase in inflammatory cells is believed to contribute to a heightened risk of breast cancer.

Impact of Childbirth and Breastfeeding

Interestingly, some studies have indicated that pregnancy and childbirth may actually reduce the risk of breast cancer in older women. The new research highlights that for first-time mothers in their 30s, the risks escalate in the immediate years following pregnancy before gradually declining over time. Additionally, factors such as the number of children a woman has and whether she breastfeeds them can also influence her cancer risk.

A meta-analysis conducted in 2020 encompassing over 50,000 women across 47 studies found that each additional year of breastfeeding per child could reduce breast cancer risk by more than 50 per cent, decreasing from 6.3 to 2.7 cases per 100 women.

Given the elevated risks associated with pregnancy at an older age, Porter advises women who become mothers in their 30s to adopt a proactive approach to their health. He recommends regular mammograms and self-examinations to detect any lumps or abnormalities early on.

As research continues to unfold, understanding the intricate relationship between age, pregnancy, and breast cancer risk remains crucial for improving health outcomes for women worldwide.