For planning and expecting moms
Still there in the morning.
You'll already be up tonight. Not for this.
Your body is doing extraordinary work right now and sleep is not always negotiable. We can't promise a restful night. What we can promise is that the pillow between your knees will still be there when you wake up — because it is sewn into the sleeve on your thigh, not loose on the bed.
Why the pillow keeps moving.
If you're planning a pregnancy or already expecting and you sleep on your side, the standard advice is to put a pillow between your knees. By the second trimester, most pregnant people are sleeping on their side, and most of them have a pillow between their knees by then. The trouble is, a loose pillow doesn't stay there. You roll, you switch sides because the hip you were on hurts, you reach down at 2 a.m. and the pillow is on the floor again.
By the third trimester you are already sleeping in shorter stretches. You're up to use the bathroom. You're up because the baby moved. You're up because your hip hurts. You do not need a fourth reason to be awake at 3 a.m. looking for a foam wedge.
Plumb is built so the pillow can't leave. The foam pillow sits inside a fitted case that is sewn permanently to the body-side of a soft knit sleeve worn on your upper thigh. When you turn, the sleeve grips the thigh and the case carries the pillow along with it. There is no separate piece to fall on the floor, because there is no separate piece. One garment. One job. Still there in the morning.
How Plumb is built.
Plumb is one garment with a foam pillow inside:
- The sleeve-and-case — a soft tubular knit (viscose made from bamboo) worn on the upper thigh of your top-resting leg, with a fitted case sewn permanently to the body-side surface. Silicone dot grippers on the inside top rim keep the sleeve from sliding. About five inches tall. The whole thing machine-washes as one piece.
- The foam pillow — a contoured hourglass foam core, CertiPUR-US certified polyurethane. Slides into the case from a body-side flap closure. Replaced as a separate consumable when it eventually wears. Two thickness options: 5-inch baseline, 6-inch for larger frames or firmer mattresses.
The sleeve stays put because it is anchored around your thigh. The foam pillow stays put because it cannot leave the case it is sewn into. The system moves as one unit through every position change — every roll, every side switch, every time you sit up to take a sip of water and lie back down.
Why this page exists.
This page is a gift in my mother's memory. She raised six kids on what she had, which was not much in the way of money but a lot in the way of heart. She would have appreciated a product company that thought about a pregnant body before it thought about a margin. So we did.
Plumb is built with planning and expecting moms in mind. The sleeve-and-case ships in two sizes — Regular up to 28 in. and XL 28–32 in. — which already cover most thigh circumferences across pregnancy. The gentle practical guidance below is what we'd tell a planning or expecting mom about how to size it and how to use it as her body changes.
A purpose-built Plumb Maternity sleeve sits on our v2 roadmap. We're not promising it as a Kickstarter backer reward and we're not taking deposits for it — the existing sleeve-and-case is what we ship first. If the Maternity sleeve becomes a real product post-launch, planning and expecting moms on our list will hear about it first.
Things worth knowing.
A few practical notes for planning and expecting moms specifically — these are observations from our wear-test cohort and from category research, not medical advice. Your provider is the right person to ask about anything specific to your pregnancy.
- Sizing changes during pregnancy. Thigh circumference often increases through the second and third trimester. If you're closer to the 28-inch boundary between Regular (≤28 in.) and XL (28–32 in.), size up rather than down — the sleeve should be snug but not compressive.
- Pillow thickness. Most adults use the 5-inch baseline. If your mattress is on the firmer side, or if you're a larger frame, the 6-inch may track better with your hips. Either thickness can be exchanged within 30 days of receiving your kit.
- Wear it on the leg that ends up on top. Most side sleepers have a preferred side; the sleeve goes on the leg that most often rests on top. If you switch sides through the night, the sleeve stays on the same leg — the geometry still works.
- Heat regulation. The sleeve is a soft knit; it breathes the way a wide compression sock breathes. We've heard back from testers that it's noticeably cooler than wrap-around-the-cushion straps. We can't make a temperature claim beyond the materials — just noting the design intent.
- Washability. The sleeve-and-case washes as one knit fabric system. The foam pillow inside doesn't — it slides out the body-side flap closure and is replaced as a consumable when it eventually wears. For a planning or expecting mom, the wash-cycle separation matters more than for most users; the contact layer stays clean, the foam stays dry.
What Plumb is not.
Plumb is a comfort and sleep-alignment product. It is not a medical device. It is not intended to diagnose, treat, cure, or prevent any disease or medical condition, and it is not a pregnancy-specific health product. If you're experiencing back, hip, or pelvic discomfort, or if you're concerned about any aspect of your sleep during pregnancy, your physician, midwife, or doula is the right person to talk to.
We say this because the knee-pillow category is full of products making claims they can't back up. Plumb is positioned as a better-designed comfort product, and that's the only promise we make.
Frequently asked questions.
Plumb's customer guarantee.
You're going to love it. We guarantee it. If you don't love your Plumb kit, send it back within 1 year of receipt for a full refund. Free shipping both ways. Defects are replaced free, anytime. Read the full guarantee →
What's Plumb's return policy?
You have a full year from when your Plumb kit arrives to decide if you love it. If you don't, send it back for a full refund — we email you a prepaid return label, and we cover shipping both ways. If the product is defective, we replace it free, with no time limit. We just ask for your order number or the email you ordered with so we can find your purchase. Applies to direct orders from plumbsleep.com; Kickstarter backers, see your Backer Update #1. Full guarantee →
Is Plumb safe to use during pregnancy?
Plumb is a knee pillow kit. It does not contact your abdomen or back, and there is nothing in the product that is contraindicated during pregnancy. That said, talk to your provider about anything you're using during pregnancy — they're the right person to make that call, not us.
When should I switch from the Regular to the XL sleeve?
If your upper-thigh circumference is approaching 28 inches, the XL sleeve is the right fit. You can exchange sizes within 30 days of receiving your kit. The sleeve should feel snug enough for the silicone grippers to engage, but never compressive or numbing — if it cuts in, it's too small.
Can I use Plumb after the baby arrives?
Yes. Plumb is designed for side sleepers regardless of pregnancy status. The kit you order during pregnancy is the same kit you continue using afterward; the only thing that may change is sleeve size, which is what the 30-day exchange covers. See the postpartum continuity section above — the corpus we read shows pregnant buyers continuing to use their knee pillows nine to sixteen months postpartum.
What about side-sleeping recommendations from my provider?
Most providers recommend side-sleeping in the second and third trimester. We don't know your provider's specific guidance and we don't substitute for it. Plumb is a comfort tool that may make whichever sleep position your provider recommends more comfortable — that's the limit of what we claim.
Won't a body pillow be more useful?
A body pillow solves different things than we do. If what you need is belly support or something to hug while you sleep, a body pillow is the right answer and we are not. If the thing keeping you up is the knee pillow that won't stay between your knees through the night, we are. Many planning and expecting moms use both — a body pillow for belly support, a Plumb for knee retention. They solve different problems.
What about partner space?
A pregnant side sleeper with a U-shaped or C-shaped body pillow can take up most of a queen mattress. Plumb is just a sleeve worn on your thigh with a foam pillow seated against your inner thigh. If sharing a bed is the goal, Plumb is the smaller-footprint answer.
Will I wake up with the pillow in the right place?
That's the whole reason Plumb exists. The sleeve anchors to your thigh; the foam pillow is sewn into a case on the body-side of the sleeve and can't separate from it. When you turn, the whole system turns with you. The Stage 1 wear test (30 nights, four side-sleeping testers) is in progress; we publish results before launch.
Is the foam safe?
The foam is CertiPUR-US certified polyurethane — the industry program that certifies foam is made without certain restricted substances and meets a low-VOC threshold. The foam is also separated from your skin at all times by the case it is sewn into, which is part of the same knit sleeve-and-case fabric system that machine-washes.
Does Plumb make a sleeve specifically for pregnancy?
Not yet. Plumb is a side-sleeper product. Many planning and expecting moms are side sleepers — that's why this page exists. We don't make pregnancy-specific health claims, and we don't position Plumb as a pregnancy medical device, because it isn't one. A purpose-built Plumb Maternity sleeve sits on our v2 roadmap; if it becomes a real product post-launch, the planning and expecting moms on our list hear about it first.
Join the launch list.
Plumb is pre-launch. We're building a small list of people who want to hear when the Kickstarter campaign opens — including planning and expecting moms who are doing this math right now and want a kit that doesn't keep moving on them.
If that's you, join the launch list at plumbsleep.com. We'll send a small number of useful updates: test results, fit guidance, launch timing, and early-backer access. No spam. No unrelated offers.