Newborn's Weight May Affect Adult Cancer Risk
Heavier Babies Have Higher Risk of Some Cancers as Adults
An infant's birth weight may predict cancer risk later in life, a new study
A study in the Feb. 7 International Cancer Journal found that
heavier birth weight babies were more likely to have cancer of the stomach,
pancreas and colon, and more likely to have blood cell cancers, compared to
infants born at lighter weights.
Heavier newborn girls have a higher risk of developing breast cancer before
age 50, says the study. The findings came from British and Swedish researchers
including Valerie McCormack of the London School of Hygiene & Tropical
The risk of developing cancer was not the same for all types of cancers.
Infants born at a higher birth weight had a lower risk of developing cancer of
the lining of the uterus (endometrial) later in life.
Other cancers -- including ovarian, cervical, and prostate cancer -- weren't
affected by birth weight.
Data came from more than 11,000 babies born at Sweden's Uppsala Academic
Hospital from 1915 to 1929. The hospital kept detailed records on each baby,
including birth weight, maternal age, birth order, length, and head
When the babies became 37-year-old adults, British and Swedish researchers
began monitoring their health records for cancer, following them for about 40
years. During that time, 2,685 cancers were registered for the group.
The researchers calculated the difference each extra pound (450 grams) at
birth made for adult- cancer risk. They factored in differences due to smoking
and variations in the number of weeks of pregnancy at the birth of each
Every extra pound at birth brought a 13% increase in digestive cancers, a
17% increase in blood cell cancers, and a 39% increase for breast cancer in
women before age 50.
For men, cancer risk rose 8% for every 450-gram increase in birth weight.
For women, increased cancer risk rose until age 50, mainly due to breast
However, heavier newborn girls had an advantage with cancer of the uterine
lining (endometrial cancer). They were 24% less likely to have endometrial
cancer, regardless of age. "Rates of this cancer in women who weighed at
least 4,000 grams (8.32 pounds) were almost half that of women who weighed
under 3,000 grams (6.2 pounds)," write the researchers.
McCormack and colleagues aren't sure how to explain the findings. Perhaps
larger birth size means more cells at risk for cancer, as some studies have
Still, smaller babies don't have all the advantages. In addition to the
increased endometrial cancer risk, the researchers say that other studies have
linked smaller birth size to increased risk of heart disease and diabetes later
There's no way to change your birth weight. But being active, following a
nutritious diet, and getting proper medical care can help your health, whether
you were a big baby or a petite newborn.