Do girls wear bras under prom dresses?

I'm curious, is it customary for girls to wear bras underneath their prom dresses? It seems like a delicate balance between style, comfort, and support. Do most girls opt to wear them, or do they forego the bras in pursuit of a more seamless silhouette? I'm genuinely interested in understanding the norms and preferences surrounding this topic, as I believe it's a common concern among those preparing for such a significant event.