Links to NCI Materials
Menopausal hormone use (sometimes referred to as hormone replacement therapy or HRT) usually involves treatment with either estrogen alone or a combination of estrogen with progesterone or progestin, a synthetic hormone with effects similar to those of progesterone.
The best evidence for the risks and benefits of menopausal hormone replacement therapy comes from the Women's Health Initiative (WHI), a large randomized clinical trial including more than 16,000 healthy women, sponsored by the National Institutes of Health (NIH).
Results from the trial published in 2002 showed that the overall risks of estrogen plus progestin outweigh the benefits. Among the risks observed after 5.6 years of follow-up were increased risks of breast cancer, heart disease, stroke and blood clots.
On March 1, 2004, after nearly seven years of follow-up, NIH stopped the estrogen-alone arm of the trial, concluding that estrogen alone does not appear to affect (either increase or decrease) heart disease, a key question of the study. In addition, estrogen alone appears to increase the risk of stroke and decrease the risk of hip fracture. No increase in breast cancer risk was observed during the study period.
- Menopausal Hormone Therapy and Cancer
(Reviewed: 12/05/2011) - A fact sheet about the results of research on menopausal hormone therapy. Includes information about the effect of menopausal hormone therapy on the body. Also outlines the benefits and risks of using menopausal hormones.
- Menopausal Hormone Therapy and Ovarian Cancer: Questions and Answers
(Posted: 10/03/2006) - In a recent study published in the Journal of the National Cancer Institute, NCI and AARP reported that five or more years of estrogen plus progestin use significantly increased the risk of ovarian cancer for women who have not had a hysterectomy.
- Increased Risk of Ovarian Cancer Is Linked to Estrogen Replacement Therapy
(Posted: 07/16/2002) - Researchers from the NCI have found that women in a large study who used estrogen replacement therapy after menopause were at increased risk for ovarian cancer.
- Uso de hormonas después de la menopausia: preguntas y respuestas
(Publicación: 9 de julio de 2002 ) - La menopausia es la transición entre los años en los que una mujer puede embarazarse y los años en los que el embarazo ya no es posible.