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[Obstetrical complications and physical aggression behaviours before the age of 2]
Raymond H Baillargeon1, Elise Thibodeau, Francine Lefebvre
1École interdisciplinaire en sciences de la santé, Université d'Ottawa, Ontario, Canada. raymond.baillargeon@uottawa.ca
Insights
Infants experiencing obstetrical complications (OCs) show more frequent physical aggression before age 2. This impact on early aggressive behavior is independent of gender and socioeconomic status, potentially explaining sex differences.
Area of Science:
- Developmental Psychology
- Pediatric Medicine
- Behavioral Science
Context:
- Obstetrical complications (OCs) can impact infant development.
- Early childhood aggression is a significant area of research.
- Understanding factors influencing behavioral development is crucial.
Purpose:
- To investigate the link between obstetrical complications (OCs) and early physical aggression in infants.
- To determine if this association is independent of gender and family income.
- To explore OCs as a potential explanation for sex-based differences in aggression.
Summary:
- Infants with Apgar scores below 7 at birth demonstrated a higher likelihood of frequent aggressive behaviors at 17 months.
- This association between OCs and aggression persisted regardless of gender or family income.
- Obstetrical complications may contribute to the observed higher rates of aggression in boys.
Impact:
- Findings suggest obstetrical complications influence early aggressive behaviors independently of socioeconomic status.
- This research provides insights into the etiology of early-onset aggression.
- Highlights the importance of considering birth complications in developmental assessments.
Objective:
To determine if infants who experienced obstetrical complications (OCs) have a greater tendency to show frequent physical aggression behaviours before the age of 2, independent of gender and family income. Another objective was to explain, at least partly, the sexual differences found in some behaviours using OCs.
Method:
Data were from the Québec Longitudinal Study of Child Development (QLSCD). OCs were measured with Agpar scores (< 7) at 1 minute following birth. Family income level—sufficient or not—was measured when infants were about 5 months old. Twelve behaviours of physical aggression, opposition defiance, and hyperactivity were measured when infants were about 17 months old. Weighted data were analyzed using hierarchical log-linear models.
Results:
Results suggest that infants with an Agpar score of less than 7 after birth are generally more likely to frequently display aggressive behaviours at 17 months, independent of gender and family income. Further, these results suggest it may be possible to explain, by OCs, the greater tendency in boys to frequently display aggressive behaviours at 17 months.
Conclusions:
Contrary to some hypotheses, it turns out that OCs have an impact on aggressive behaviours before the age of 2 independent of socioeconomic status.
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