You’ve stayed with us for the last few weeks as we explored hormone replacement therapy, and now we finally get to the biggest concern we often hear from women: “Won’t it cause breast cancer?”. Multiple independent studies from 1986 through 1995, and even some as late as 2006 have shown that there is no relationship between hormone replacement therapy (HRT) and breast cancer.
The study published in 1995 looked at data collected from 121,700 registered nurses from 1976 through 1992. The results showed women who had used HRT at any point- even those that had taken it for more than 10 years- had no increased risk of breast cancer. With all these reassuring findings, what happened?
In 2002 the National Institutes of Health shocked the medical world by halting their studies on hormone replacement due to “an increased risk of invasive breast cancer.” HRT fell by up to 70% and panic ensued. Women were left confused, scared, and were likely no longer being prescribed the medication they needed.
Here are the things that were not published: 1) the increase in breast cancer did not meet statistical significance (instead of 5 women in 100 getting breast CA, the use of HRT increased it to 6 in 100. Oh, and they also left out that the women on HRT that did develop breast CA had better outcomes than the women who developed breast CA and were not on hormones.) 2) In 2006 the study updated their findings to say that the alleged risk had vanished .There was no shocking press release for these findings. 3) In 2010 the WHI reviewed their findings AGAIN and determined now that women on HRT had an increased risk of death from breast CA but the data once more was not clinically significant (2.6 on HRT vs 1.3 per 10,000 women. For some context, the risk of breast CA goes up to 4.9% with electric blanket use – weird, right)
If nothing seemed clinically significant, why the panic, confusion, and discontinuation of hormones that helped thousands of women? Simple. There was an agenda to “stop the hormone bandwagon” that the principal investigators FELT was out of control. They also knew, as evidenced in later dialogue, that a study of this magnitude could never be repeated so the results would be what they say they are and “the statistical police will need to leave the room.”
There you have it, the rise and fall of HRT. The use of estrogen has never fully recovered since the 2002 publications that were inaccurate and deceiving. Whether HRT is right for you is not for us to say. Our hope is that we have empowered you with knowledge so that you can be your best advocate and engage in an honest conversation with your health care provider about the realistic risks and benefits of HRT.
-Brooke Rieth NP