I believe you mean the breast cups and not champgne glasses.
She had them made for her Rambouillet pleasure Dairy farm, and ordered them at the famous Sèvres porcelain company. The cups had the shape of a female breast and it was rumoured that Marie Antoinette had the cups made from a mould of one of her own breasts.
This is highly unlikely though, for she was known as a very prude woman, who even bathed in a huge robe so her ladies in waiting did not get to see her naked.