Once you've settled on a shape and figured out how to position it, the fill material inside is what actually determines how the pillow feels night after night — and it's easy to overlook while comparing shapes and sizes.
Memory foam: contoured support, less adjustable
Shredded or solid memory foam holds its shape and contours closely to wherever you're resting against it, which makes it the most supportive option for consistent pressure relief through the night. The tradeoff is less adjustability — memory foam doesn't reshape as easily if you shift positions often, and it can retain more body heat than looser fills.
Polyester fiberfill: lightweight and easy to reshape
Polyester fiberfill is the lightest and most breathable option here, and it reshapes easily every time you move, which suits anyone who changes position several times a night. It compresses more over time than memory foam, so it may need occasional fluffing or earlier replacement to keep its original loft.
Microbead: adaptive but divisive in feel
Tiny foam or polystyrene microbeads shift and conform closely around your body, offering a distinctive, almost liquid-like support that some people find deeply comfortable and others find unusual. It's worth trying in person or reading fill-specific reviews before committing, since reactions to microbead fill vary more than with the other two materials.
Cover fabric affects how the fill actually feels
Even the same fill material can feel different depending on the cover — a cotton jersey cover breathes more and feels cooler against skin, while a plush velvet-style cover traps slightly more heat but feels softer to the touch. If temperature regulation matters to you specifically, weigh the cover fabric alongside the fill rather than treating fill choice as the whole decision.
Match fill to your actual sleep habits, not just comfort in theory
A back-and-side sleeper who shifts positions often will get more consistent comfort from fiberfill's easy reshaping than from memory foam, which takes a moment to re-contour each time. Someone who finds one comfortable position and stays there most of the night will likely get more out of memory foam's sustained support.
Browse Maternity Pillows to compare fill types alongside the shape and size you've already narrowed down.
Before you choose a fill
- Choose memory foam for sustained, contoured support if you mostly hold one position
- Choose polyester fiberfill if you shift positions often through the night
- Try microbead fill in person or check fill-specific reviews before committing
- Match fill choice to your actual sleep habits, not comfort in the showroom alone
Conclusion
Shape gets a pregnancy pillow into the right position, but fill material is what determines how it actually feels through a full night of real movement. Compare fill types in Maternity Pillows.