I have never heard of such nonsense in my life. I read about these on a breeder site and found it hard to believe, but a simple google search shows this is the popular and newest trendy little artsy keepsake for preggos. They actually make a cast of their pregnant body including swollen belly and udders and then paint it all up in cutesy little colors with pink bows and such and display them as artwork.
Below is a bit from one of the sites I found and it has a "gallery" of some of the finished products.
'Welcome to Mommy's Belly belly casts. A site devoted to the art of belly casting. Belly casting (belly masking/belly sculpture), is the process of creating a plaster mold of a mother's belly during pregnancy. Imagine physically capturing the beauty of an expectant mother's belly, which can be shared with her child for years to come. The belly casting process is simple and takes only about 45 minutes to complete, but the result is a piece of art which can last a life-time.
..... For those looking to give the creme de la creme in mother-to-be gifts, Mommy's Belly proudly offers the Mommy's Belly Ultimate Spa Belly Cast Kit....."
Take a few moments to browse Mommy's Belly belly cast Gallery to see examples of how other people have created and decorated their belly casts........."
I do not get this kind of "art" at all.