Yes - any treatment can lose efficacy over time . There is currently no research about the ongoing efficacy of GnRHa treatment in those with PMDD/PME. Although is it not fully understood why this may be the case, with some people clinically it is noted by members of the IAPMD Clinical Advisory Board that they do see patients who do well to begin with an GnRHa initially but find that over time it does not continue to suppress the ovarian function as well as at first.
These medications must suppress ovulation to be effective. If you believe that you are still ovulating, you can use at-home urine LH surge tests to determine whether you are ovulating. If you find that you are still ovulating, be sure to share this with your physician, as it means that you have not had a “fair trial” of treatment since it was not effective in producing a menopausal state.
To confuse matters further, some patients can experience anovulatory cycles (this is when your ovaries do not release an egg, meaning you could experience fluctuations without an ovulation). This means that the GnRHa treatment was only partially working. It is vital you track your symptoms carefully to try to make sense of what is occurring if you are still having cyclical symptoms.