Menopause is a time when
women suffer from symptoms like hot flashes and sweating due to decreased
levels of the sex hormones in the body. The symptoms are generally relieved
with the use of estrogens. However, estrogens do have their side effects and
are not always recommended.
Following hysterectomy i.e. a surgery to remove the uterus, a condition
similar to menopause develops. Estrogens are used to relieve symptoms in these
cases as well.
In a trial called Women's
Health Initiative trial, the use of estrogens in post-hysterectomy women was
studied. More than 10,000 postmenopausal women from the United States were
enrolled in the study in the period between 1993 and 1998. These women were
aged between 50 and 79 years, had undergone hysterectomy, and did not suffer
from breast cancer. Among these, 5310 women received 0.625 mg of conjugated
equine estrogen, while the rest received a placebo. The study had to be
terminated earlier than planned due to an increased risk of stroke. The women
were followed up for duration of around 11 years.
Researchers found that use of estrogen for around 5 to 6 years was
associated with a lower incidence of invasive breast cancer in the long run as
compared to placebo. Women who took estrogen and developed breast cancer were
less likely to die from the cancer or any other cause as compared to those who
did not take estrogens.
The benefits of estrogen in
these women were mainly noticed in those at low risk for breast cancer, such as
those without benign breast disease or family history of breast cancer.
The results thus indicate that women undergoing hysterectomy who are at
low risk for breast cancer could undergo estrogen treatment for a duration of
around 5 years.
However, the researchers do not recommend the use of estrogen with an aim of
reducing breast cancer risk.
studies on this topic have yielded different results. Some studies have
indicated that estrogens increase breast cancer risk; others say that they do
not alter breast cancer risk, whereas the current study shows a beneficial
The results of the study do
not apply to women who have not undergone a hysterectomy or those who take a
combination of estrogen and progesterone hormones.
equine oestrogen and breast cancer incidence and mortality in postmenopausal
women with hysterectomy: extended follow-up of the Women's Health Initiative
randomised placebo-controlled trial; Garnet et al; The Lancet Oncology; Early
Online Publication March 2012