Many seamstresses have asked us for the size of the 23" My Twinn  Doll bodies... and the answer is there is quite a bit of variation... just like with real kids :)  

chest  13" to 16"

waist 12.5" to 15.5"

hips 14.5" to 16"

The good news is that with the soft fabric bodies there is some give for fit, but sometimes waists are just too large and chests too broad for good 'generic' fit. The best bet is to measure your doll(s) and adapt your pattern to fit your range of sizes before cutting your fabric.  We would love if pattern drafters for these dolls would take into account the variation in sizes and mark their patterns for different size bodies.

The following are a fairly good sampling of the ranges of body sizes: