Hi Emily,
I agree with Brandie on this wholeheartedly. This is a problem any number of us face or have faced, especially since many manufacturers shifted from plastic-faced products to the "new & improved" densely woven 'fabric/breathable' lines. As they - laudably - shifted away from plastic, too many went cheap and eliminated the waistbands...the one-time "gold standard" for European-designed products is infamous for this foolish action...and the fit has proven inadequate. If you do find yourself relying on a 'fabric' product might I suggest extending the tapes by way of 1-inch plastic or fabric tape, available at most supermarkets/drugstores, especially if the Velcro tapes become loose too often. Hope this helps a little.