1940s Pattern Sizing
In the early 1940s, not much has changed from the 1930s in pattern sizing, aside from dropping the reference to "years". Categories remain the same: Women, Miss, Junior or Junior Miss, Girls, Children, Infants, Boys, Men. However, we begin to see the Junior Miss with odd numbers for sizes, while Miss sizes are even numbers. But as the decade progresses, pattern manufacturers begin to pay attention to figure types. This will result in some fine tuning of sizes, as described below.
This summary of body sizes is from the Butterick Sewing and Dressmaking book from 1944.
The 1944 Butterick Sewing and Dressmaking book provides these descriptions of different body types: Full, Tall Angular, Short Full, Junior Miss, Miss, and Average. While at this point, pattern sizes don't address the tall angular or the short full figures, it points the way to the half size patterns that begin to appear later in the 1940s and the future "proportioned" patterns that will appear in the 1950s. It also points out that the Junior Miss is a type not an age - an important distinction.
Sizes in a 1948 Vogue book on sewing are similar to the sizes described in the Butterick book, but shortens Junior Misses to Juniors.
A Simplicity sewing booklet from 1949 adds Teen and Half Sizes to the list of body types, and actually provides more detail to explain the differences. This is the first time we see the Half Size, which is a great addition that addresses the needs of women with a shorter than average body type.
Note how Woman's sizes are essentially identical to Misses, but simply extend to higher sizes and provide both youthful and "mature" (also referred to as "matronly", meaning older than "Miss") designs.
Pattern manufacturers continue to produce their patterns in compliance with government-defined standards (extremely important during World War II), but the addition of body types is a great acknowledgement that we all aren't "average". The beginning of producing pattern sizes that address those different body types is a boon to seamstresses in reducing the amount of work to adjust a pattern to fit.
I hope this information helps those of you sewing 1940s vintage patterns. Just keep the proportions in mind as you purchase and sew patterns from this decade. And knowing the differences can allow you to purchase a pattern in a size type that you might not normally purchase for yourself (Teen or Junior Miss for example), with an expectation of how you can alter it to fit.