Tamoxifen is recommended for five years following treatment for certain types of breast cancer. Previous research has shown that the drug reduces the risk of disease recurrence by 47 percent and the risk of death by 26 percent.
While the drug is not thought to damage fertility itself, women must stop taking it if they wish to become pregnant because it is teratogenic.
Researchers Dr Jacqueline Jeruss, from the University of Michigan in Ann Arbor, and colleagues found that 35 percent of patients who either refused to take tamoxifen or discontinued treatment before five years cited fertility concerns as the reason.
'With this information, what we hope we will now be able to accomplish is a targeted intervention that is in line with current guidelines... that state that patients should be referred to a fertility specialist at the earliest possible time point in their diagnosis,' Dr Jeruss told MedPage Today.
In the study, the researchers reviewed the medical notes of 515 premenopausal women with breast cancer for whom tamoxifen was recommended.
They found that, overall, 13 percent of patients declined tamoxifen and a further 16 percent stopped treatment before five years.
The most common reason for refusing or discontinuing tamoxifen was concern or experience of side effects, recorded for 36 and 69 percent of these patients, respectively.
However, the researchers also found that women who expressed at the time of diagnosis that they wanted to preserve their fertility were five times more likely to decline tamoxifen than other women. These women were also 78 percent more likely to discontinue tamoxifen within five years if they did begin taking it.
These findings were also confirmed when then researchers conducted telephone interviews with 88 patients who did not start or discontinued therapy, with 35 percent citing fertility concerns as their primary reason.
'Our study points toward the importance of fertility to young breast cancer patients,' commented
Currently, women who want to become pregnant while taking tamoxifen are advised to take the treatment for two years before having a break to have a child. However, it is currently unclear what effect that has on the effectiveness of the drug. A large, international trait, known as POSITIVE, is currently underway to attempt to resolve this question.