For all CiCi's existing customers, we advise going up a size.
For in-between sizes, we also recommend you size up.
CICI SIZE AU/UK US HIPS
XS 4-6 0-2 33 in
83 in

S

8 4
35 in
88 cm
M 10-12 6-8
37-39 in
93-38 cm
L 14-16 10-12
41-43 in
103-108 cm
XL 18 14-16
45 in
113 cm
 
Seamless BRIEF is true to size. 
Seamless THONG runs small. We recommend going up a size.