SAN FRANCISCO — In surprising study results, a health researcher has found a new risk factor for breast cancer: a woman's unresolved sexual conflicts, from adolescence through menopause.
Peggy Boyd, associate researcher at UC Medical Center in San Francisco, studied 180 pairs of sisters.
Those who had not resolved adolescent conflicts about their sexuality were more than twice as likely to have developed breast cancer than their siblings who dealt with the conflicts, she found.
In addition, most of the cancer-stricken sisters were less aware of their body's changes during puberty and menopause than the healthy women.
Age, race, income and family history of breast cancer are already understood to be important risk factors in the disease that afflicts some 120,000 American women each year, killing 40,000.
Psychological, Social Factors
Boyd's study centered on the role of psychological and social factors.
"A woman can have almost exactly the same genetic and socioeconomic risk factors as her own sister and still be at many times greater risk of developing breast cancer," said Boyd, who conducted the study while a doctoral student at UC Berkeley.
"Unresolved adolescent conflicts about sexuality inflict a silent wound that in later life can increase a woman's susceptibility to disease, including breast cancer."
She cautioned that health professionals should not accuse women of increasing their cancer risk and women who develop breast cancer should not blame themselves.
"It is most important that women talk about their own bodies and sexuality to help reduce their risk," said Boyd, who describes her findings in a new book, "The Silent Wound: A Startling Report on Sexuality and Breast Cancer."
To ensure that the sisters' early family experiences were as similar as possible, she chose pairs who were no more than fours year apart in age. Half the afflicted sisters were older and half younger than their healthy sibling.
Awareness of Body Changes
In most pairs, the researcher found, the sister with cancer was less aware of her body's changes during puberty, including secondary sex characteristics such as growth of pubic hair, and during menopause, including weight gain and loss of breast elasticity.
The cancer-stricken sisters more often reported negative attitudes about their bodies, specifically their breasts, stemming from adolescence through adulthood.
Many also remembered feeling in competition with their mothers during puberty and being unable to discuss their emotional conflicts about sexual maturity.
"If a woman does not come to terms with her adolescent conflicts, they may intensify and through neuroendocrine, immunological or other mechanisms weaken her resistance to disease in later life," Boyd said.
"A woman, who by virtue of her ethnic background, early development, economic status, urban location or childlessness is already at an increased risk of developing breast cancer, might want to look at her own adolescent experience and the resulting attitudes toward her sexuality that are influencing the way she thinks and behaves right now."
No One Cause Identified
While no one cause for breast cancer has yet been identified, Boyd said, awareness is growing that factors such as diet, child-bearing age and even age when menstruation begins can be manipulated to reduce a woman's cancer risk.
"I am convinced that women can gain some control over their susceptibility to breast cancer," Boyd said.