From your history it seems that you might be having local fungal infection
During period due to wet and some un-hygeniec surrounding there might be more precipitation of fungal infection.
Apply anti-fungal cream.
Take oral anti-fungal tablet like Flucanozole 150 mg once in a week for4 weeks.
tablet for itching.
Keep local hygiene clean, dry and airy, particularly during period.
Ok and take care.