Yes, you can participate in pūjā while on your period.

In Jain Dharma:

• There is no concept of “ritual impurity” of the body during menstruation that would stop you from doing pūjā, samayik, pratikraman, mantra‑jap, reading scriptures, or going to the temple.
• Menstruation is a natural physical process, not a paap (sin) and not a reason to stay away from Bhagwān.

What you can keep in mind:

• If you feel physically weak or in pain, you may do lighter sādhanā (like mental pūjā, pāth, or listening to pravachan) instead of long or physically demanding rituals.
• Some families or local communities follow old customs asking women to avoid certain rituals during periods. These are social customs, not a Jain śāstric rule. Follow them only if you freely choose, not out of fear of “dosha”.

Spiritually, your bhāv (inner feeling) is what matters in Jainism. With shuddha bhāv and after normal daily cleanliness/bath, you may do pūjā as usual, even during periods.