White discharge before period is a common and natural part of the menstrual cycle. Hormonal changes, especially increased progesterone levels, can cause vaginal discharge to become thicker, creamy, or milky white in the days leading up to menstruation. In most cases, this discharge helps keep the vagina clean and protected from infection. However, if the discharge has a strong odor, unusual color, or is accompanied by itching or irritation, it may indicate an infection or another health concern.