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

Preterm infants have a high risk of cranial deformity resulting from external pressures. Such deformity is associated with delayed neurodevelopment. We aimed to clarify the effects of continuous use of positioning pillows on cranial deformity and neurodevelopment in preterm infants. 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. 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). Continuous pillow use in preterm infants is effective in reducing cranial deformity and improved cognitive and fine motor skills. UMIN Clinical Trials Registry, trial no. UMIN000034400 (http://www.umin.ac.jp/ctr/index.htm). •Preterm infants have a high risk of asymmetric cranial deformity.•Such deformity is related to delayed development and asymmetrical motor function.•Positioning pillow use in preterm infants effectively reduces cranial deformity.•The pillows further improve cognitive and fine motor skills.