In Jainism, the question of how sadhvis (female ascetics) manage menstruation is treated with caution and varies by tradition (Digambar vs. Śvetāmbara). Here is a simple, traditional overview:

• General idea: Menstruation is viewed as a natural bodily process. Monastic rules emphasize cleanliness, discipline, and appropriate conduct during this period.
• Śvetāmbara nuns (sadhvis): Practices during menstruation can include limiting participation in certain formal spiritual activities (for example, some sangha routines like long samayikas or specific rituals may be adjusted). They typically observe heightened personal hygiene, simple meals, and adherence to the discipline of their order. The exact restrictions can vary by the specific temple or monastic community.
• Digambar tradition: Digambar monastics have different codes of conduct from Śvetāmbara. In many traditional Digambar rules, women do not become Digambar monks, and the rules for sadhvis are shaped by their own lineage. The emphasis remains on purity, reflection, and restraint, but the concrete practices during menses can differ from Śvetāmbara practice.
• Core point across both traditions: The emphasis is on maintaining spiritual focus and moral discipline, rather than on strict punitive rules. If a sadhvi feels the need, she may observe stricter personal discipline, take extra rest, or adjust her daily regimen in harmony with her council (us) and temple guidelines.
• Important caveat: Exact practices are not universal across all temples or lineages. Digambar and Śvetāmbara communities, and even different ashrams within a tradition, may have their own customary practices and interpretations.

If you’d like, I can point to Jain scriptures or reputable Jain sources that describe traditional monastic codes and how they are applied in practice, keeping in mind the Digambar–Śvetāmbara differences.