The effect of infant feeding methods and non-nutritive sucking behaviours on speech sound development at age five years

Burr, Sam

Abstract

Children with speech sound disorders (SSD) constitute the largest population of referrals to speech and language therapy (SLT) services (Broomfield & Dodd, 2004). This study aims to identify potential early risk factors for SSD at the critical ages of two-five years by investigating the relationship between different infant feeding regimes (exclusive breastfeeding, bottle and mixed feeding), non-nutritive sucking (NNS) and motor development of speech in early childhood. If a relationship is identified, this will support parents to make informed care choices from birth onwards, as well as reinforcing national public health messages and maximising positive long-term health and social outcomes for children. This study contains three independent but related strands. Strand One used data from the Avon Longitudinal Study of Parents and Children (ALSPAC) to investigate the relationship between feeding, NNS and speech development at ages two and five in a longitudinal cohort study. Strand Two collected data as part of the ALSPAC Generation Two study (ALSPAC-G2) to look at feeding, NNS and speech development in two- to four-year-olds. Strand Three used NHS SLT clinical caseload data to investigate the feeding histories of children aged two-five years diagnosed with SSD and determine whether a greater proportion were exposed to one particular type of feeding regime and/or NNS than would occur in the general population. Children participating in Strands Two and Three completed detailed standardised speech sound assessments. Data on potential confounding variables for speech was collected and included in the analysis. Speech articulation skills and phonetic inventory were described in detail and statistical analysis undertaken to identify differences between groups of children fed by different methods and with different NNS behaviours. Relationships between variables, and specifically the role that feeding and NNS plays in the speech development of children with and without SSD, were explored. The study found that different patterns of feeding and NNS were associated with different speech sound outcomes between ages two-five years. Longer duration of exclusive breastfeeding was indicated to be associated with reduced parental concern about speech at age 18 months. Associations between feeding and specific consonant sound errors were observed. Exclusive breastfeeding was found to be associated with markedly reduced likelihood of alveolar sound errors at age 5 years compared with exclusive bottle feeding. Although some association between NNS was not shown to have an impact on speech sound development at age 5 years. The findings of this study were explored in the context of relevant theoretical mechanisms for sucking and speech sound development. Implications for clinical practice and public health messaging are described, and recommendations for future research are outlined.

• Thesis Type: Thesis
• Deposit Date: May 17, 2022
• Publicly Available Date: Nov 14, 2022
• Keywords: infant feeding, breast feeding, bottle feeding, dummy, non-nutritive sucking, speech sound development, speech sound disorder
• Public URL: https://uwe-repository.worktribe.com/output/9504023
• Award Date: Nov 14, 2022