Letrozole questions (Femara)

Pauline 🌈 • Eleven angels in heaven. "Somewhere, over the rainbow, skies are blue..."
I know the risk of multiples is much lower with letrozole than with clomid, but does anyone know if increasing the doseage of letrozole increases chances of multiples? I'm on 2.5 mg now but will be increasing if things aren't successful..any higher chance of twins with 5 mg?