Baby clothes sizing?

Keely • 27 living in Madison,WI pregnant with our second set of twins...no ivf...just God!

Hi Ladies! Still have to get our twins a few more onesies and rompers. Wondering if I should get newborn or 0-3 months? Most of the clothing we have now is 0-3 months. I'm at 33 weeks now and babies are already almost 5 lbs each.

Any thoughts?