Voice therapy needed to counter the "Marilyn Monroe" effect
Routine voice therapy is needed for children who were intubated when they were born very preterm to reduce their risk of developing speaking difficulties, according to recent research.
Scientists from UWA, ECU and Princess Margaret Hospital assessed the voices of 20 school-aged children who were born at less than 32 weeks' gestation.
Most of these children were intubated at birth to help them breathe however the tube, which is about the same size as the babies' windpipes, can cause structural problems with the voice box, or laryngeal pathology.
The researchers conducted a clinical voice assessment and a laryngeal assessment to determine how these children's voices differed to a normal voice.
UWA speech pathologist Victoria Reynolds says as part of the assessment a small camera was inserted either through the child's nose or mouth, and hovered over the voice box as the child performed speaking tasks.
"When we ask the child to speak we can have a look at how the muscles and the vocal folds are behaving when the child talks," Ms Reynolds says.
While the study produced varied results due to the individuality of participants, Ms Reynolds says there were some similarities.
"All the children unfortunately were having a lot of trouble getting their vocal cords to close properly during talking, so it means there's a lot of extra air coming out when they're talking so their voices can sound a bit breathy and a bit weak," she says.
"Think of a voice like Marilyn Monroe, which is great if you're a woman and you're in your thirties.
"But for a young boy aged 13 or 16 or if you're a young boy or girl aged seven or eight in a noisy playground, that's much more problematic because it's really hard to shout and make yourself heard."
The researchers also found all the children examined were squeezing their voice box muscles very tightly when they spoke, which they believe is due to the vocal folds not coming together.
"When we squeeze our muscles too tightly to talk it actually gives our voices a strained quality," Ms Reynolds says.
"What that does with the preterm children, it actually makes their voices sound worse than they would from the structural pathology alone."
Ms Reynolds says there is no way to avoid intubation as it saves the children's lives, but behavioural therapy, which works to change the behaviour associated with using the voice, might help them to relax their voices.