What are the Pre- and Perinatal Risk Factors for Deformational Plagiocephaly? A Systematic Review and Meta-Analysis

Objective To identify pre- and perinatal risk factors associated with deformational plagiocephaly (DP) in infants. Design Systematic review and meta-analysis followed PRISMA and the PECOS framework, with searches in Oct 2024 (updated Apr 2026). Study quality was rated with the Newcastle-Ottawa Scale, meta-analysis was conducted in RevMan, and evidence certainty was assessed using GRADE. Setting Studies published in international peer-reviewed journals and identified through electronic databases and grey literature sources. Participants Pregnant women and their infants included in cohort and case–control studies, comparing those exposed and unexposed (or less exposed) to pre- and perinatal risk factors, with the perinatal period operationally restricted to the interval between the 22nd gestational week and delivery. Intervention Not applicable. Main Outcome Measure Occurrence of DP diagnosed during infancy. Results Thirteen studies comprising 31,147 pregnant women and/or infants were included, of whom 3993 (12.9%) were diagnosed with DP. Prematurity (<37 weeks), multiple pregnancy, male sex, and maternal age ≥35 years were significantly associated with increased risk of DP ( P < .05). Although samples were representative with adequate follow-up, methodological limitations were noted, including insufficient control for confounding and heterogeneity in diagnostic criteria. The certainty of evidence for all associations was rated very low. Conclusions Prematurity, multiple pregnancy, male sex, and advanced maternal age represent potential risk markers for DP. However, the certainty of the current evidence is very low, and these findings should be interpreted with caution. Further studies with stronger methodology and standardized diagnostic criteria are needed to clarify these associations.