New Study: Having a Large Baby Raises Risk of Breast Cancer

?Having a large baby can increase your risk of getting breast cancer? Sounds outrageous, right? Well new research shows that women who give birth to larger babies are twice as likely to be at risk for breast cancer, as opposed to woman who have smaller babies.

The study was published by PLoS ONE, lead by Dr. Radek Bukowski, the professor ob obstetrics and gynecology at the University of Texas’ Medical Branch. 

They suggest, having a larger, heavier baby, can create a hormonal environment in pregnancy that can eventually lead to the development of breast cancer. Previous studies have linked baby’s birth weights with mothers risk to breast cancer later in life. This current study aims to separate the association from other risk factors, like the heaviness of the mother (since that has a direct effect on a baby birth weight).

What exactly did the study entail? 410 women were followed for seventeen years. All of these women gave birth to their first child while participating in the study. All breast cancer risk factors were recorded and considered, including age when menstrual cycle started, age at menopause, race, body mass index, etc.

During this seventeen year period, 31 women were diagnosed with breast cancer.  Women who had babies born in the top fifth of weight were 2.5 times more likely to be diagnosed with breast cancer. Difficult breast cancer risk factors, such as, women’s weight, family history, and hormone usage were all adjusted for.

In another, larger study by First and Second Trimester Evaluation of Rish for Aneuploidy, otherwise known as FASTER, suggests that women who gave birth to the largest babies (8.25 lbs or bigger) were found to have had a “pro carcinogenic environment.”