For flat nipples, a thin silicone contact-style nipple shield in the right size will give your baby the best chance at a deep, effective latch. The shield works by creating a longer, firmer shape over your breast that reaches the roof of your baby’s mouth and triggers their natural sucking reflex. Getting the size right matters more than the brand, but a few products are specifically designed with flat nipples in mind.
How a Nipple Shield Helps With Flat Nipples
A nipple shield sits over your areola and nipple like a thin cap, with tiny holes at the tip where milk flows through. For flat nipples, it solves the core problem: your baby needs something firm and protruding to latch onto, and a flat nipple doesn’t provide enough of a target. The shield acts as a second nipple, giving your baby a defined shape to latch around.
When the shield’s tip touches the roof of your baby’s mouth, it activates the sucking reflex that flat nipples alone may not trigger. Flat nipples are the single most common reason parents use nipple shields. In one review published in Breastfeeding Medicine, 62% of mothers using shields reported flat nipples as the primary reason.
What to Look For in a Shield
Modern nipple shields are made from ultra-thin medical-grade silicone. This is the only material worth considering. Older rubber and latex versions were thicker, which blunted nipple stimulation and interfered more with hormonal signals that drive milk production. Thin silicone largely solved that problem. The shield should be flexible enough to conform to your breast but firm enough at the tip to hold its shape when your baby latches.
Contact-style shields have a cutout section at the base, so part of the shield is removed and your baby’s nose and chin touch your bare skin during feeding. This skin-to-skin contact helps maintain your milk supply signals and can make the feeding experience feel more natural for both of you. Most shields sold today use this design.
Why Size Is the Most Important Factor
A poorly sized shield will slip, cause pain, or reduce milk flow, no matter how good the brand is. Shield sizes are measured in millimeters and refer to the inner diameter of the nipple tunnel (the narrow cone portion). Your nipple should move freely in and out of this tunnel without rubbing the sides. If your nipple drags against the tunnel walls, go up a size. If your areola gets pulled into the tunnel and it pinches, go down a size.
Most brands offer shields between 16mm and 36mm. Common starting sizes for flat nipples tend to be on the smaller end (16mm to 21mm) because flat nipples have a smaller protruding diameter, but this varies widely. The simplest way to check your size is to measure the diameter of your nipple at the base (not including the areola) and match it to the shield’s inner diameter, leaving about 1 to 2mm of space on each side for movement.
Some brands offer a wider range of sizes than others. Medela, for instance, sells five sizes (21, 24, 27, 30, and 36mm), while Elvie offers three (21, 24, and 28mm). If you fall between sizes or have particularly small or large nipples, look for a brand with more options so you can dial in the fit.
Shields Worth Trying for Flat Nipples
- Lansinoh Contact Nipple Shields: These are frequently recommended for flat nipples specifically. They use the contact-style cutout design, come in two sizes (20mm and 24mm), and are widely available in pharmacies. The silicone is thin and flexible, and the smaller 20mm option works well for nipples that don’t protrude much.
- Haakaa Nipple Shield: Designed as a one-size-fits-most option, this shield is made from soft silicone and has a rounded shape that conforms to different breast sizes. It’s often cited as a strong choice for flat and inverted nipples because of its flexible fit.
- Medela Contact Nipple Shields: The widest size range on the market (five sizes) makes these a good option if you need a very specific fit. The thin silicone and contact cutout are standard features.
If your first shield doesn’t feel right, try a different size before switching brands. Fit issues are almost always a sizing problem, not a design flaw.
How to Apply a Shield to a Flat Nipple
Getting the shield seated properly on a flat nipple takes a slightly different technique than on a protruding one. The most effective method is sometimes called the “sombrero” technique: partially turn the shield inside out so the tip folds inward, press it onto your nipple, then let it flip back into shape. As it flips, it creates gentle suction that draws your flat nipple up into the shield’s tunnel. This gives your baby a better target from the very first latch.
Dampening the edges of the shield with a few drops of breast milk or water before applying it helps it stick to your skin and reduces slipping during the feed. If the shield slides around, that’s usually a sign it’s too large or not getting enough skin contact at the base. A well-fitted shield should stay in place without you holding it.
The Trade-Off: Milk Transfer Efficiency
Nipple shields do reduce the amount of milk removed per feeding session. A mechanistic study found that pumping with a properly fitted shield removed roughly 25% less of the available milk compared to pumping without one. In practical terms, median pumped volume dropped from about 77mL without a shield to 32mL with one.
This doesn’t necessarily mean your overall milk production will tank. In the same study, 24-hour milk production was similar between groups (around 620 to 650mL per day), suggesting that more frequent feeding or pumping can compensate. Still, this is why lactation professionals recommend monitoring your baby’s weight gain and wet diapers while using a shield, and why shields work best as a bridge rather than a permanent solution.
Transitioning Away From the Shield
The goal for most parents is to eventually breastfeed without the shield. After a week or two of consistent shield use, your nipple tissue often becomes more protractile (meaning it stretches out more readily), which can make direct latching possible for the first time.
A practical way to start the transition is to remove the shield partway through a feeding, once your nipple has been drawn out by the suction and your baby is already in a rhythmic sucking pattern. Your baby may latch directly onto the now-protruding nipple without missing a beat. Some babies resist this at first, and that’s normal. Try it once per feeding session without forcing it.
If direct latching continues to be difficult after several weeks, working with a lactation consultant can help. They can assess your baby’s latch mechanics and mouth anatomy to rule out other factors like tongue tie that might be making the transition harder.