Impaired coordination and incomplete emptying may increase the risk of leakage. “If there's a little bit of overflow, then you can have a little bit of incontinence and leakage that goes up there too,” Fosnight said.
She also emphasized the role of bowel function, which is commonly affected in hypothyroidism. “The other thing to think about is constipation, because everything…is slowing down,” she said. “When you have constipation and fullness of the rectum, that's going to put extra pressure on the pelvis and the bladder.” That added pressure can further interfere with bladder emptying and worsen urinary symptoms.
Metabolic changes associated with hypothyroidism may compound these effects. “Metabolism can slow down too, and we may see more body composition changes,” Fosnight said. “So increased adipose tissue in the central part.” Central adiposity, she noted, “can increase the intra-abdominal pressure and putting pressure on the pelvic floor and the bladder, and that could worsen those urinary symptoms.”
Despite these plausible mechanisms, urinary symptoms related to thyroid dysfunction are often overlooked. “We haven't really been taught how much the endocrine system, especially thyroid, affects the pelvic organs,” Fosnight said. “It is really easy to say, ‘Somebody's been pregnant or somebody has had a vaginal delivery.’ ”
She cautioned against normalizing symptoms without adequate evaluation. “Even though this may be something common, it doesn't necessarily mean that this is a normal thing that we should actually just let go by the wayside,” she said.
Fosnight also pointed to gaps in care during menopause and perimenopause. “We are giving out localized hormone estrogen cream, and maybe that gets things a little bit better,” she said. “But this estrogen cream is getting me 50% better, but if we improved my thyroid or we looked at some other things, maybe I could get 80% better.”
She believes sociocultural expectations play a role. “Women have been taught to just be happy with any improvement rather than going, well, how far can we go?” Fosnight said. She added that meaningful change will require broader shifts in medical education and practice. “Until things change too, from a medical perspective, from a provider standpoint, we're not even going to be able to help and advocate for our patients to make those changes.”