Pre-1975 Birth Control Pill May Have Increased Risk of
Breast Cancer for
Some
Women with a family history of breast cancer may have
an
increased risk if they took birth control pills before 1975,
a new
study reports.
The study of 426 women, conducted by the Mayo Clinic
and
reported in the Journal of the American Medical Association,
found
that sisters and daughters of women with breast cancer
were three times more
likely to get the disease if they took
birth control pills prior to 1975. The
risk of breast cancer
was increased 11-fold for pill-using women from
families with
five or more family members with breast cancer.
The study found no increased risk of breast cancer among
the
granddaughters and nieces of cancer victims -- possibly the
result of
the newer pill's lower doses of the hormone
estrogen, which is thought to
foster the growth of some
breast cancers. However, the researchers
noted that the
younger generation, whose average age in the study was
43,
may have been too young for cancer to have developed.
When asked
about the study and its possible consequences for
women presently taking a
birth control pill, Dr. Clifford A.
Hudis, Chief of the Breast Medicine
Service at Memorial
Sloan-Kettering, noted, "This affects older birth
control
pills using much higher doses than any that are
prescribed
now. It also affects a subset of women -- those that have
a
family history of breast cancer."
"The real take-home message is
that a woman taking a modern
birth control pill should not conclude from this
study that
she has any special increased risk of breast cancer," Dr.
Hudis
concluded. "And birth control pills may protect against
ovarian cancer, which
can be more difficult to detect and
treat."
The study can be found in
the October 11, 2000 issue of the
Journal of the American Medical
Association:
http://jama.ama-assn.org/issues/v284n14/abs/joc00479.html
