Can I use the sauna if I’ve got my period? 

Klafs Wellness FAQ

In general, there is no reason why a woman should not use the sauna during her period. If your periods are too light, using the sauna regularly can improve your condition by increasing the flow of blood to the uterus. Using the sauna can also help to relieve period pains, since warmth has a soothing effect on cramp-like pain; many women use heat cushions for the same purpose. Take care, however, when cooling down after the sauna, and refrain from Kneipp practices. During your period, you should exercise caution when cooling down, and not hose down your stomach area with cold water.