An UNIGE team has found that maternal voice can help reduce the perception of pain in preterm infants undergoing medical procedures.
An infant born earlier than 37 weeks of gestation is considered preterm. Approximately 15 million preterm infants are born every year worldwide. Moreover, around 1 million children each year die from preterm birth complications. These include low birth weights, neurodevelopmental delay, respiratory problems, and even chronic health issues. As a result of the complications, preterm infants move to the neonatal intensive care unit (NICU) to receive specialized care. Care includes being placed in an incubator, having a feeding tube, and sometimes even blood transfusions. These medical interventions can be distressing for the infant, and painful. Now, researchers have found an unlikely solution to the painful experience of a preterm infant: maternal voice.
As preterm infants receive care in the NICU, they undergo separation from their parents for long periods of time. This prolonged separation can further add to the infants’ stress levels and affect their social and emotional well-being later in life. Previous studies have shown that the presence of a parent can have a calming effect on these babies. Thus, to further study this effect, researchers from the University of Geneva (UNIGE), in collaboration with the Parini Hospital in Italy and the University of Valle d’Aosta, conducted research. The study aimed to evaluate the effects of maternal voice on an infant’s pain perception and oxytocin levels.
We demonstrate here the importance of bringing parents and child together, especially in the delicate context of intensive care.
Dr. Manuela Filippa, study author
Talking vs Singing
The research followed 20 preterm infants at the Parini Hospital in Italy. Mothers of the infants were asked to be present during the daily blood test. The researchers compared the infant’s response under three phases: the presence of the mother, mother singing, and a third with the mother taking. According to the study author, Professor Didier Grandjean the mother talked or sang five minutes before, during, and after the procedure.
We also measured the intensity of the voice, so that it would cover surrounding noise, as intensive care is often noisy due to ventilations and other medical devices.
Professor Didier Grandjean, study author
A Preterm Infant Pain Profile (PIPP) helped assess the preterm infant’s pain with the help of facial expressions and physiological signs like a heartbeat. Results showed a PIPP of 4.5 in the absence of the mother. This dropped to 3 when the mother talked. Thus, showing that a mother’s voice can have a significant effect on the infant’s pain perception. Furthermore, the PIPP was higher (3.8) when the mother sang. The researchers believe the difference occurred because talking alters the mother’s voice more than singing.
Maternal Voice Raises Oxytocin Levels in Preterm Infant
The researchers also evaluated the oxytocin levels in the infants using a painless saliva sample. They took the sample before the mother spoke or sang, and after the prick. Results showed a significant increase in the level of oxytocin when the mother spoke.
Thus, showing that the oxytocin levels act as a protective mechanism in preterm infants for early pain perception.
Furthermore, parents play a protective role here and can act and feel involved in helping their child to be as well as possible, which strengthens the essential attachment bonds that are taken for granted in a full-term birth.
Professor Didier Grandjean, study author
Reference:
Filippa, M., Monaci, M.G., Spagnuolo, C. et al. Maternal speech decreases pain scores and increases oxytocin levels in preterm infants during painful procedures. Sci Rep 11, 17301 (2021). https://doi.org/10.1038/s41598-021-96840-4
