The 3371 has deep cups for Chantelle. If you are wearing another brand it could run differently. If you are wearing a UK based brand such as Fantasie, Freya or Panche their cup sizing runs differently than the US sizing. Please see Universal Cup Size, HerRoom Site.
Arrin B. from Grand Rapids, MI
If you are spilling out of the cups the cup is to small. If the cup is too small the overall fit will be compromised and will be uncomfortable. The side panels move breast tissue from the side and centers and forward while the trasversal seam rounds. We would suggest trying Chantelle Bastille bra 3991
3 part cup which offers a lower wire underneath the arm which should be more comfortable for you.
Nisserhop from Las Vegas, nv