I resonated with oopsiedaisy's opinion. If there is no follow-up therapy after Evenity, future bone turnover will rely on your body's natural balance between resorption and formation.

With the secondary cause of bone loss addressed (removal of the parathyroid tumor, and assuming your bone remodeling has reset to pre-hyperparathyroidism levels), the primary cause, estrogen deficiency, still remains.

Many postmenopausal women in their 70s may see a natural slowing of bone resorption, which might be helpful. However, a gradual decline in bone formation is almost inevitable with age unfortunately. The balance between these two opposing processes may not always support a healthy bone turnover or maintenance.

Personally, i'd lean toward a short-term course of an antiresorptive, with close monitoring of bone turnover markers as you transition off medication if you could. Even a low dose of estrogen could be considered (full disclosure - I'm a bit biased, as I'm currently using it myself after Forteo). Unlike bisphosphonates though, it does need to be taken continuously to maintain its benefits.

Please keep us posted on your journey if you can. Wishing you continued good health and all the best on your bone health journey.