Background: Obstetric brachial plexus palsy (OBPP) is a birth injury that affects upper extremity per-formance. However, some children with OBPP might have central nervous system disorder or develop-mental disabilities. This study aimed to investigate (1) the early spontaneous movements using General Movements Assessment (GMA) in infants with OBPP according to the Narakas classification, (2) the differences from typical infants, and (3) the relationship between the GMA and the affected upper ex-tremity movements score.Methods: Fifty-six infants with OBPP (39 females; median gestational age 40 weeks, range = 34 to 42) and 50 typical infants (20 females; median gestational age 38 weeks, range = 37 to 41) were assessed at age three to five months using the GMA, which is a determined Motor Optimality Score (MOS) for fidgety movements and concurrent motor repertoire, and using the Active Movement Scale (AMS) for affected upper extremity movements.Results: There were no differences in MOS and its subcategories between Narakas types in infants with OBPP (P > 0.05); however, infants with OBPP had a higher degree of aberrant fidgety movements and a lower score in MOS and its subcategories than typical infants (P < 0.05). There was no relationship between AMS scores, and MOS and its subcategories.Conclusions: Infants with OBPP, except Narakas type I, might have an increased risk of central nervous disorder and developmental problems in addition to peripheral nerve injury. Each test, GMA and AMS, contributes to the identification of their own specific risk in these infants.(c) 2022 Elsevier Inc. All rights reserved.