Refractory PMDD: GnRH Agonist + Add-Back
A GnRH agonist can shut down the ovarian cycle driving her PMDD entirely — the progestin needed to protect her uterus from unopposed estrogen is the same class of hormone her PMDD may already be sensitive to.
K.W., a 38-year-old logistics manager, has had DRSP-confirmed PMDD for nine years, with severe irritability, tearfulness, and intrusive thoughts of worthlessness confined to the ten days before each period — symptoms severe enough that she has taken intermittent unpaid leave from work during particularly bad cycles. She has failed both continuous and luteal-phase-only sertraline at adequate doses, and a subsequent trial of fluoxetine dosed continuously produced only marginal improvement before she stopped it for persistent nausea. She has an intact uterus, no history of endometrial disease, and no other chronic illness.
Her gynecologist and psychiatrist are now discussing a GnRH agonist, leuprolide, specifically to suppress ovarian hormone cycling entirely — PMDD is understood to be a response to the normal cyclical rise and fall of ovarian hormones rather than to any hormonal abnormality, and removing the cycle itself has real evidence of resolving PMDD symptoms where SSRIs have failed. Suppressing estrogen for an extended period carries its own risks, chiefly bone density loss, which is why GnRH agonist therapy for this indication is paired with add-back hormone therapy to replace enough estrogen to protect her bones without restoring the cyclical swings driving her symptoms.
The complication is specific to her anatomy and to PMDD's own proposed mechanism. Because she has an intact uterus, unopposed estrogen add-back would raise her risk of endometrial hyperplasia, which ordinarily argues for adding a progestin to protect the endometrium — standard practice in any other add-back regimen. But PMDD is increasingly understood to involve an abnormal central nervous system sensitivity to allopregnanolone, a progesterone metabolite, which means the progestin added specifically to protect her uterus is a plausible route back to the exact mood symptoms the GnRH agonist was started to eliminate. The choice isn't between a safe option and a risky one; it's between two different real risks, protecting her endometrium or protecting her mood stability, with no add-back regimen that cleanly avoids both.
At the combined endocrine-psychiatric consultation
Leuprolide with estrogen-only add-back is the cleanest way to protect her mood stability, but I can't recommend it without a progestin given her intact uterus — unopposed estrogen over any meaningful duration is a real endometrial hyperplasia risk, not a theoretical one, and that's not a tradeoff I'd make to avoid a symptom that might not even reappear at add-back doses rather than full physiologic cycling doses.
The dose distinction the endocrinologist is pointing to matters pharmacologically — add-back progestin doses are meant to be low and steady specifically to avoid recreating the cyclical hormone swings that drive PMDD, which is a different exposure than her normal menstrual cycle ever gave her. It's a real, evidence-based reason to expect a lower risk of symptom recurrence than her history alone would predict, though not a guarantee.
Continuous low-dose levonorgestrel or a levonorgestrel IUD are both options that keep systemic progestin exposure especially low and steady, which may be the more favorable choice for a patient with her specific sensitivity history compared to a cyclic or higher-dose oral progestin.
Given how severe and treatment-resistant her PMDD has been, I'd rather start with the levonorgestrel IUD specifically — it protects the endometrium locally with minimal systemic progestin exposure, and if her mood symptoms return anyway, we'd have real information that even the lowest-exposure option triggers her sensitivity, rather than starting with a higher-exposure oral progestin and not knowing which variable caused a relapse.
Leuprolide was started as monthly depot injections, with add-back deliberately deferred for the first two to three months so that suppression alone could be tested before any hormone was added back — starting estradiol and progestin on day one would have made a persisting symptom impossible to attribute. Transdermal estradiol and a levonorgestrel IUD follow once that read-out is in. Daily symptom ratings continue throughout, scored as a running severity record rather than by cycle phase, since suppression removes the menses the DRSP normally anchors to.
The regimen continues, with bone density monitored at the standard interval for extended GnRH agonist use.
That result would itself be clinically informative — pointing toward an estrogen-only add-back with a different endometrial-protection strategy, or reconsidering how sensitive her particular presentation is to progestin at any exposure level.
The team was explicit with K.W. that this regimen was chosen to minimize, not eliminate, the mood-symptom risk from add-back progestin — and that her own symptom diary over the coming months would be the actual test of whether that tradeoff worked, not a guarantee made in advance.