I have been wanting to write some information on how a leotard should fit, when I stumbled across this great article from www.thedancewearguru.blogspot.com.au
Many first time dancers and first time dance parents are unsure of how a leotard is supposed to fit, which often leads to dancers showing up to class in items that are too large. The truth is that leotards are supposed to be snug. Take a look at the models on discountdance.com. They all model leotards that appear smooth on their bodies with no sags or wrinkles from extra fabric. If you are familiar with elite swimming or gymnastics, you will notice that swimmers and gymnasts wear tight suits and leotards that hug their bodies without any extra room. This represents an appropriate fit.
Leotards should not be so tight that they ride up above the hip bones, ride down and show excessive chest or cleavage, or cause unreasonable irritation around the arms and legs. However, leotards that are too loose to hug the bottom or have loose straps are definitely too big.
It’s common for a child to try on a leotard for his or her first ballet class and come out of the fitting room saying “too tight.” In most cases, the leotard is not actually too small; the child must become used to wearing tight fitting garments if he or she is going to be successful in dance. Almost all children will acclimate to wearing dancewear within two weeks or so. It is appropriate for children under eight years old to have a tiny bit of “growing room” in their leotards (a small amount of wrinkling down the front/length or a small bit of looseness in the sleeves, but not looseness in the bottom or shoulders). Growing room is a common result of a child being between sizes, NOT a license to purchase dancewear a whole size too big. That will only make it more difficult for a child to participate in dance class. Dancers over eight years old should have snug leotards with no extra room.
If a dancer has sensory issues, cotton leotards and styles with sleeves sometimes feel better than camisole or spandex styles in the same size. Note that many brands of leotards run on different sizing scales, so it’s difficult to judge whether or not something will fit appropriately based on its designated size. If a dancer normally wears a medium leotard in one brand, he or she may need a small or a large in another brand to get a good fit.
Dancers should always try on leotards if they can. Putting on a leotard, spending a good amount of time examining it in a mirror, and moving around to check the fit are the best ways to ensure that a leotard fits appropriately. After trying on a few styles and sizes, dancers should always choose the tightest fit in which they feel comfortable.