The other thought is that maybe it is fungal without being
yeast per se.
Estrogen levels go up and that is often linked to
yeast and fungal overgrowth. I would try to change undies often, wear only cotton, let yourself air dry at night, eat or take a probiotic supplement or enhanced food (like yogurt or the drinks), and cut down on sugar. Your doctor is not wanting to treat you for a yeast infection? That itching must be a pain!