Short answer: Yes. A girl (or any Jain practitioner) can recite the Navkar Mantra even during menstruation, as the mantra is a personal prayer of reverence and does not require entering a temple or performing temple-specific rituals. The restriction during periods is generally about temple entry and certain acts, not about the ability to chant Navkar at home with devotion. The key is sincerity, humility, and mindfulness.

Details you may find helpful:

• Traditional period-related restrictions in Jain practice often concern temple entry and certain rituals, but do not abolish personal devotional recitation like Navkar in many communities. You would usually chant Navkar at home or in a clean, respectful space. ( jainknowledge.com)
• The Navkar Mantra itself is a simple, devotion-based recitation. Its vidhi emphasizes devotion, humility, and inner purity rather than elaborate ritualism. Chanting with devotion is the core idea. ( jainknowledge.com)
• There are variations between Digambar and Shwetambar practices on many ritual details, but reciting Navkar with proper bhav (attitude) remains central in both traditions. If you follow a specific lineage, consult your guru for any local conventions.

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