Recently I was asked if you could raise the crotch in a pair of pants. Well, yes and no. In either case it’s not going to be a quick alteration.
If the pants are gigantic you may be able to do a quick and dirty fix (figure 1). You could try adjusting the angle of the inner side seam to cut out some of the crotch area. Pretty simple. Don’t forget that some of that fabric was allotted to make room for your rear end. If you take in the inner leg seam you may end up altering your pants to give you a wedgie.
So what else can you do? I have yet to find an easy solution. You could try removing the waistband and lowering it (figure 2). This will shorten the distance between the crotch and waistband. This trick only works if the pant legs are long enough. Otherwise you will look like you are preparing for a flood.
Why does this problem exist? No two pairs of pants are created equally. Ideally, manufacturers should give you the inseam, outseam, and waist measurements. But, we all know they don’t (and definitely not in women’s pants). If they did, people would not be suffering from the saggy crotch issue (or the plumbers crack issue from a crotch that is too short).
If you are prone to the saggy crotch (in most cases this is usually because you wear your pants lower than your natural waist) you may want to try low rise jeans. [Rise is the term that the manufacturers use to note the distance between the crotch and the waist (or the difference between the inseam and the outseam).] If you don’t make your own clothes, you are just going to have to shop around (and you shouldn’t rely on a manufacturer to maintain their proportions from year to year unless they have a specific style like levi’s. Levi’s don’t seem to have messed around with the fit of the individual styles. They tend to add new ones instead). By now most people know that sizes are definitely not standardized across manufacturers.