Effects of continued positioning pillow use until a corrected age of six months on cranial deformation and neurodevelopment in preterm infants: A prospective case-control study

Background: Preterm infants have a high risk of cranial deformity resulting from external pressures. Such deformity is associated with delayed neurodevelopment. Aims: We aimed to clarify the effects of continuous use of positioning pillows on cranial deformity and neurodevelopment in preterm infants. Methods: This prospective case-control study was conducted between November 2018 and August 2019. The continuous use of a pillow was initiated after discharge from the neonatal intensive care unit, up to a corrected age of six months. Preterm infants weighing less than 1800 g without neurological abnormalities were included in the study. Patients were divided into two groups: non-pillow group (NP-group) and pillow group (P-group). The primary outcome was the Bayley Scales of Infant Development III (BSID-III) score. We compared asymmetrical cranial deformity and the BSID-III scores in the two groups at a corrected age of six months using the Fisher's exact test and unpaired t-test, respectively. Results: There were 19 preterm infants (mean gestational age 32.5 +/- 1.9 weeks, birth weight 1461.3 +/- 244.7) eligible during the study period. The P-group (n = 11) showed asymmetrical cranial deformity at six months less frequently than the NP-group (n = 8) (p = 0.001, Fisher's exact test). Infants in the P-group had significantly higher scores on the BSID-III cognitive scales (95.0 +/- 8.4 vs. 86.9 +/- 2.6; p = 0.02, unpaired t-test) and fine motor scores on the motor scales (8.6 +/- 2.2 vs. 6.6 +/- 0.7, p = 0.02, unpaired t-test). Conclusions: Continuous pillow use in preterm infants is effective in reducing cranial deformity and improved cognitive and fine motor skills.