How old you are may affect your daughter's cancer risk

New study makes shocking revelations; links health of the girl child to the age of the father.

A father's age at the time of his daughter's birth may affect her risk for breast, ovarian and endometrial cancer in adulthood, according to a new study.

Women born to a father under the age of 20 had a 35 per cent greater risk of breast cancer and more than two times greater risk of ovarian cancer, when compared to those born to a father whose age at his daughter's birth was 25 to 29 years old, researchers found.

"Our findings indicate that parental age, especially paternal age, at conception appears to be associated with a wide range of effects on the health and development of the offspring," said lead researcher Yani Lu from City of Hope in the US.

To help determine the effects of parental age on the risk of adult-onset hormone-related cancers, Lu and her colleagues examined a cohort of 133,479 female teachers and administrators from the California Teachers Study.

Between 1995 and 2010, 5,359 women were diagnosed with breast cancer, 515 women were diagnosed with ovarian cancer and 1,110 women were diagnosed with endometrial cancer.

While the team of researchers did not find an association for maternal age at birth for any type of cancer, they found that paternal age is linked to an increased adult-onset cancer risk for daughters -- and the link was not only to advanced paternal age.

Women born to a father under the age of 20 had a 35 per cent greater risk of breast cancer and more than two times greater risk of ovarian cancer, when compared to those born to a father whose age at his daughter's birth was 25 to 29 years
old.

Women born to a father whose age at childbirth was 30 to 34 years had a 25 per cent greater risk of endometrial cancer than those born to a father age 25 to 29.

Lu and her team were not surprised to find a relationship between older fathers and an increased risk of hormone-related cancers, especially since there has been increasing evidence suggesting that daughters born to older fathers have increased risk of breast cancer, noted Lu.

However, there have been no previous studies that examine the effects that young paternal age has on a daughter's breast cancer risk or the effects of parental age on the risk of ovarian cancer and endometrial cancer.

"We observed that young paternal age, as well as advanced paternal age, increase the risk of breast cancer. We also found that young paternal age increases the risk of ovarian cancer," Lu said.

The findings were presented at the American Association for Cancer Research's annual meeting in San Diego.