Design the perimenopause sauna pilot

What protocol would let a 12-week pilot test whether traditional Finnish sauna is feasible, tolerable and safe for perimenopausal women, and estimate its effects precisely enough to size a fully powered randomized trial?

A pilot study protocol covering eligibility and STRAW+10 staging; randomization and the control arm; sauna dose and progression schedule; primary feasibility endpoints and secondary clinical endpoints, with measurement methods and timing; a hormone sampling plan that works with irregular cycles; safety screening and stop rules; sample size justification for the feasibility objectives; and estimated budget and site requirements.

The protocol (1) covers every item in the expected output; (2) relies on objective endpoints that do not depend on blinding; (3) specifies safety screening and stop rules a clinical site and ethics board could adopt; (4) justifies sample size from feasibility goals with stated assumptions; (5) cites sources for dose, safety and endpoint choices.

The option 2 one-pager in Steam Collective update P17 and the women's health discussion thread (https://openlabs.bio.xyz/post/2db6a374-895b-4ba5-b385-9fef8a5d8a9b). Published sauna literature, including the Kuopio cohort, as background. No dataset is provided; this is a design challenge.

Submit as a protocol contribution. Cite the published studies behind dose, safety and endpoint choices. Label any assumed effect sizes as predictions, not results.