Women who receive aromatase inhibitors for breast cancer after menopause experience very high levels of sexual difficulties. These difficulties include low interest, insufficient lubrication, and pain with intercourse. The authors of this study, published online in Menopause, state that this is an important and underestimated problem.

This study is the first to look at the impact of this type of breast cancer treatment on specific aspects of sexuality in postmenopausal women. The researchers are from Örebro University and Uppsala University in Sweden. They used a standardized questionnaire to assess sexual function.

Nearly three quarters of the women being treated with aromatase inhibitors had insufficient lubrication, 56% had pain with intercourse, half said their sexual interest was low, and 42% were dissatisfied with their sex life. These percentages were much higher than for postmenopausal women who were not being treated for breast cancer, regardless of hormone use (P<.05). Although women taking tamoxifen for breast cancer also had low sexual interest and more pain with intercourse (31.3%), their difficulties were significantly fewer than those for women taking aromatase inhibitors.

Aromatase inhibitors block the formation of estrogen from other hormones in the body, and they may offer advantages by preventing breast cancer and possibly increasing survival. These advantages may lead to increased use of aromatase inhibitors in the future. Unfortunately, effective treatment options for their sexual side effects are lacking. The authors pointed out that too much estrogen may be absorbed from vaginal estrogen treatments. The authors called for more intensive study of the causes and impact of these side effects so that the quality of life can be improved for breast cancer survivors in the future.