The cause of functional speech sound disorders is not known; however, some risk factors have been investigated.
Frequently reported risk factors include the following:
- Gender—the incidence of speech sound disorders is higher in males than in females (e.g., Everhart, 1960; Morley, 1952; Shriberg et al., 1999).
- Pre- and perinatal problems—factors such as maternal stress or infections during pregnancy, complications during delivery, preterm delivery, and low birthweight were found to be associated with delay in speech sound acquisition and with speech sound disorders (e.g., Byers Brown, Bendersky, & Chapman, 1986; Fox, Dodd, & Howard, 2002).
- Family history—children who have family members (parents or siblings) with speech and/or language difficulties were more likely to have a speech disorder (e.g., Campbell et al., 2003; Felsenfeld, McGue, & Broen, 1995; Fox et al., 2002; Shriberg & Kwiatkowski, 1994).
- Persistent otitis media with effusion—persistent otitis media with effusion (often associated with hearing loss) has been associated with impaired speech development (Fox et al., 2002; Silva, Chalmers, & Stewart, 1986; Teele, Klein, Chase, Menyuk, & Rosner, 1990).