Yes, you can take a treatment like Canesten for vaginitis during pregnancy. It is recommended to use a 6-day treatment to minimize side effects like irritation. You can apply the cream inside the vagina at bedtime for 6 days, as well as on the external intimate areas twice a day for better effectiveness. Symptoms should improve within 2-3 days and completely heal after 1 week. If symptoms persist or return within 2 months, it's important to see a healthcare professional.