How do I find a maternity swimsuit that doesn't make me look like a beached whale?
The more tailored the maternity clothes, the thinner you will appear, and this extends to swimwear, as well. If a bathing suit has ruffles and large amounts of gathers, you'll appear larger. When there is more fabric, it looks like there's more of you!
So look for ribbed fabrics that have a vertical direction. The striping effect will make you appear taller. V-fronts also help give the illusion of a thinner you. Choose a dark bottom, and you'll appear smaller on the bottom, too.