Introduction:
When selecting a nipple for an infant, ensuring the nipple flow rate aligns with an infant’s developmental skills is crucial for safe, effective feeding. When flow rates are too fast, increased too quickly or without clear signs of readiness, it can cause detrimental effects, such as:

• stress, fatigue, incoordination of suck-swallow-breathe and reduced self-regulation (Pados et al., 2017; Jackman, 2013)
• increased risk for aspiration and AsBsDs events at bedside (Matthew, 1991)
• hindered growth and development of facial muscles needed for feeding and speech skills as the infant gets older (Sheppard et al., 2007)
• development of maladaptive behaviors, such as munching on the nipple and drooling liquid from the mouth (Eishima, 1991; Capilouto et al., 2019)
• increased risk for developing an oral aversion (Chang, 2007)
• increased length of stay (Haynes et al., 2025)

Selecting and maintaining appropriate nipple flow rates encourages skill mastery, promotes safe and efficient feedings, and supports the infant’s overall well-being. It also supports the neurodevelopmental processes of feeding, which often occurs naturally for infants who are breastfed.

We recommend all infants start on the slowest nipple flow rate available. Using Dr. Pados’ data, which can be found here, we recommend starting with nipples that are objectively found to fall within the category of “Extremely Slow Flow.” This matches the flow rate of breastmilk on DOL 1-5 from a breast. This flow rate allows infants to slowly integrate breathe into their suck-swallow patterns, ensuring safety, efficiency and stress-free learning.

As an infant matures, they will show clear signs that they are ready to move up to the next nipple flow rate category “Very Slow Flow.” Use the AFFIRM Criteria to ensure you transition to a faster flowing nipple at the most appropriate time for the infant.

Following a Family-Centered Care approach is necessary for an infant’s long-term success. Therefore, discuss the findings from the AFFIRM Criteria with the family and the medical team before making any changes. Educating parents on the AFFIRM Criteria will help them after discharge as they continue to increase nipple flow rates. The AFFIRM Criteria can also be used to educate families about why their infant should stay on a slow flow nipple.

Remember: Changing flow rates without strong, individualized rationales can be detrimental, leading to feeding and swallowing issues, undue stress, and delayed oral feeding progress.