The Supplemental Nursing System (SNS): Feeding at the Breast When More Is Needed

There are moments in a breastfeeding journey where a parent desperately wants to nurse, but their baby needs more milk than the breast is currently providing or baby is able to adequately transfer at each nursing session.. Maybe supply is temporarily low. Maybe the baby is struggling to gain weight or efficiently transfer milk. Maybe they're working through a latch issue or recovering from time in the NICU. Whatever the reason, the idea of moving to bottles feels like giving up on breastfeeding, and for many families, it doesn't have to be.

That's where a Supplemental Nursing System can be so incredibly useful!!

What Is a Supplemental Nursing System?

A Supplemental Nursing System, commonly called an SNS, is a device that allows a baby to receive additional milk (supplement) while nursing at the breast. It consists of a small container that holds expressed breast milk, formula or donor milk, connected to a very thin, flexible tube. The tube runs along the breast and sits just at the nipple, so as the baby latches and suckles, they draw both from the breast itself and from the supplemental milk through the tube, simultaneously.

The result: the baby gets the volume they need, the breast continues to receive the stimulation it needs, and the nursing relationship is preserved better than using bottles for supplements.

When an SNS Can Be a Game-Changer

Low Milk Supply

This is one of the most common reasons families turn to an SNS. When supply is not yet where it needs to be (due to a slow start, hormonal factors, difficult birth, a history of breast surgery, lack of early adequate stimulation or other causes) a baby may not be gaining weight adequately on breast milk alone. Rather than shifting entirely to bottle feeding, an SNS allows supplementation to happen at the breast, protecting the nursing relationship while ensuring the baby is getting enough.

Induced Lactation and Adoptive Breastfeeding

For parents who are inducing lactation (whether for an adopted baby, a surrogate birth, or a same-sex partner wanting to share in feeding) the breast may produce little or no milk initially. An SNS is frequently used in these situations so that nursing can begin and bonding can happen at the breast, even as supply is being built over time.

Relactation

If breastfeeding was interrupted (perhaps due to illness, a NICU stay, or a difficult early period) and a parent wants to rebuild their supply after a gap, an SNS can support that process. The baby continues to nurse and stimulate the breast while still receiving enough milk to thrive, giving the body time to catch up.

Babies Who Need Encouragement to Nurse

Some babies, particularly those who have spent significant time with a bottle, may fuss at the breast because the flow feels too slow or the effort feels too great. An SNS can increase flow just enough to reward their effort and keep them engaged at the breast, making nursing feel worth it to them while the underlying dynamics are addressed.

Oral Dysfunction or Poor Milk Transfer

If a baby has structural or functional oral challenges (tongue tie, high palate, low tone, or other issues) they may be working hard at the breast but not transferring milk efficiently. An SNS can ensure they're adequately nourished during the assessment and treatment process, without abandoning breastfeeding altogether.

What Makes the SNS Different From a Bottle

When a baby feeds from a bottle, the breast receives no stimulation. Supply doesn't increase. The nursing relationship doesn't grow. And for a baby who has developed a preference for the fast, easy flow of a bottle, more bottle time often makes returning to the breast harder.

With an SNS, every feeding is a breastfeeding. The baby is at the breast. The breast is being stimulated. The hormonal feedback loop (oxytocin, prolactin) is activated with every nursing session. The SNS supports the goal of breastfeeding rather than working against it.

Is the SNS Complicated to Use?

Honestly? There is a learning curve. The tubing needs to be positioned correctly, the flow rate needs to be appropriate for the baby, and the device itself requires cleaning and maintenance. Many families feel overwhelmed the first time they use one, and that's completely normal.

This is exactly why an SNS should be introduced and managed with the support of a trained lactation professional. Used correctly and consistently, most families find their rhythm with it. Used without guidance, it can feel frustrating and difficult to sustain.

The SNS Is Usually Part of a Bigger Plan

Like a nipple shield, an SNS is typically a bridge tool, one piece of a larger care plan designed to move you toward your feeding goals. It is rarely meant to be permanent (though for some families in certain circumstances, longer-term use is appropriate). The goal is usually to build supply, resolve the underlying issue, and gradually reduce supplementation as breastfeeding becomes more robust.

Your IBCLC can help you track how that progress is going, adjust the plan as things change, and know when it's time to start weaning back from the SNS.

If You Think an SNS Might Help You

If you're supplementing and hoping to protect or grow your milk supply, if you're inducing lactation, if your baby is struggling to transfer enough milk, or if you're just trying to hold the breastfeeding relationship together through a difficult stretch, an SNS might be exactly the right tool for this season.

But please don't navigate it alone. This is one of those situations where professional, individualized support makes an enormous difference.

Educational Videos:
How to set up SNS: https://www.youtube.com/watch?v=dNByCZstP-U
How to use SNS: https://www.youtube.com/watch?v=HgjiiB6ca-k

Ready to Get Support? I'm Here.

I offer in-home and in-office lactation consultations for families across Northern Virginia and the surrounding area, including:

Aldie · Middleburg · Purcellville · Leesburg · Ashburn · Sterling · Herndon · South Riding · Chantilly · Manassas · Warrenton

Not local? Virtual consultations are available for families anywhere. A video visit can accomplish far more than you might expect, and many insurance plans cover lactation support regardless of location.

Whether you're considering an SNS, already using one and feeling lost, or somewhere in between, I would love to help you find a path forward that works for your baby and your family.

👉 Book a Consultation or reach out with questions. There's no situation too complicated, and no question too small.

Demi Lucas IBCLC, PMH-C, Doula | Kindred Milk Lactation | Serving Northern Virginia & Virtually | Hello@KindredMilk.com