Infant Suck Strength Exam: Introduction of an Accessible Clinical Technique for Measuring Infant Suck at the Breast

One of the core skills required in lactation support is understanding and correcting ineffective or painful breastfeeding. The behavior being corrected, however, occurs inside the infant’s mouth, making it difficult to see and assess. When providing care in the field, we use standardized tools and digital suck exams. In research, instruments have been developed to measure infant suck strength with a pacifier, bottle, or at the breast using ultrasound. The aim of this article is to introduce a simple manual clinical technique to identify areas of weakness in an infant’s suck and describe one treatment option that can be used to reduce weakness in the identified area. During the Infant Suck Strength Exam, the lactation support provider places a finger on the breast 2 to 4 cm from the edge of the infant’s mouth at the upper and lower lip and then at both corners of the mouth, testing the strength of the suck in each of these four areas. To address any specific areas of weakness, the nursing parent can be taught to apply light skin traction back toward the chest wall at the affected area. This engages the suckling reflex and amplifies the strength of the infant’s suck in that particular area. The traction applied should not indent the breast but rather just pull back on the skin. It should be applied with enough strength to challenge the infant without pulling the breast out. This is a teaching tool, and is typically only needed for a few weeks before the infant improves their nursing habits.