New study finds HRT increases women’s risk for kidney stones

Hormone replacement therapy (HRT) is blamed for increasing a woman’s risk of breast and ovarian cancer, heart attacks and strokes. Now, a new research study shows the pills also increase women’s risk of developing painful kidney stones.

The landmark government research studied 24,000 postmenopausal women taking either HRT or placebo, and found that women on HRT were 21 percent more likely to develop kidney stones over a five-year period. The risks were equal among women taking Prempro, pills containing estrogen plus progestin, and Premarin, estrogen-only pills. Comparatively, studies show that overall about 6 percent of postmenopausal women develop kidney stones.

It is yet more bad news for women who for years had been fooled by false advertising from pharmaceutical companies that promised the pills not only relieved annoying symptoms of menopause, including hot flashes and mood swings, but also protected them against cancer, heart disease and osteoporosis. However, a major study into the mortality and morbidity of postmenopausal women was abruptly halted in 2002 when data indicated that women who used HRT were at substantially greater risk of developing breast cancer.

As the data was more closely studied, evidence surfaced that HRT also didn’t protect women against heart disease, and in fact, put them at greater risk or heart attacks and strokes. It was also found to increase a women’s risk for dementia and increase the death rate among women with lung cancer.

Kidney stones are hard crystals of calcium or other substances that separate from liquid in urine. The stones usually pass without treatment, but even the smallest stones can cause excruciating pain until they break up or exit the body. Stones too large to pass are often treated with noninvasive shock wave therapy or surgery.

Researchers say are uncertain why HRT increases a woman’s risk though one explanation may be that the pills can cause an increase in uric acid which may contribute to the formation of kidney stones.