Women who take the most common form of hormone replacement therapy (HRT) experience a hearing loss of 10 to 30 percent more than those who do not.
A study of 124 women showed that age-related hearing loss is accelerated for those whose HRT includes progestin, a synthetic form of progesterone.
Women who took progestin had the hearing loss usual for women up to a decade older.
The study compared the hearing of three groups of women aged 60 to 86. 30 had taken a form of HRT that included only estrogen; 32 had taken both estrogen and progestin; and 62 had never been on HRT. Each of the women was given a variety of hearing tests.
In all the tests, women whose HRT included progestin (the most common form) had worse hearing.