Hello ma am and welcome. Yes, sweat could irritate the already sensitive region, but I doubt that sweat would be the sole reason for the presentation of this sore. If your doctor has suspected a hormonal cause, and also taking into consideration your age and the expected pre-menopausal changes, this could in fact be due to your hormone levels. In such a scenario, I would suggest you to request your doctor to prescribe hormone replacement therapy which should take care of the night sweats which may be causing the sore and also the hormone imbalance caused by menopause, and thus should help heal the sore. This would be a good approach, and would be recommended by me. I hope this helps. Best wishes.