This is for everyone who has ever bought a vintage skirt, dress, or blouse, thinking you could wear it, brought it home and maybe it's too large in the bust or to small in the waist. So I hope this information helps you. Most important, you have to know your measurements.
Especially if you buy online. Modern Sizes, such as 10, 12, 20, etc, do not relate to any clothing before 2000. (Note: I'm saying that a modern size 8 in 2015 is unlikely to be the same as a size 8 in 1995.)
Modern standard commercial sizes, such as size 8, 10, 12 etc. relate to clothing being sold on the market now. In 2009, an article was published, Developing Accurate Industrial Standards to Facilitate Production in Apparel Manufacturing Based on Anthropometric Data, if you like a little "light" reading this gives you idea how clothing manufacturers globally, develop standard sizes. http://onlinelibrary.wiley.com/doi/10.1002/hfm.20148/pdf
This is why, you need to know your accurate measurements to wear clothing made years ago. Often, these clothes were tailor made for an individual, just like wedding dresses are tailored today. Manufactured clothing sizes changed based on populations and growth statics. So standards changed, see the article above if you would like more details.
So can we wear vintage clothing? Yes, but we must first find out if we can fit into those dresses by first determining our measurements.
The best way to do this is by a using a sewing tape measure. Since I sew and my mother was a tailor, this comes second nature to me. However, most of you, may not be aware of how to go about this procedure. (This is very important to understand, even when your shopping for modern day bras to get a good accurate fit. ) I have attached a link to an excellent photo and step by step guide from simplicity pattern site showing you step by step where the measurements should be taken and how to take them.
When shopping online for vintage clothing be sure that the listing gives you good measurements. Make sure that you can contact the shop owner to get more information. Do not hesitate to contact the shop owner. Most vintage sellers are very helpful and will be glad to assist you.
Two final notes:
Firstly, make sure you are wearing the undergarments that you normally wear when taking your measurements. This way you will have accurate measurements and no surprises when you put on that dress you've bought.
Secondly, give yourself 1/2 to 1 inch of breathing room in the waist and bust. Vintage shop owners, often take measurements flat on the garment. This means that the measurements are taken from seam to seam or side to side. Then the measurement is doubled to account for 2 sides, a front and back. I've checked a flat measurement with my sewing form and they almost match. However, you are not a sewing form, you need to breathe. So allowing at least 1/2 inch difference in the listing should help, depending on how the measurements were originally taken.
Ultimately it is up to you and how loose or tight you want the dress to fit.
I hope I've helped. Good hunting and good measuring.