Age-occurrence and interconnection of pelvic-perineal injuries in prepubertal and adolescent survivors of sexual abuse in conflict-affected settings: a retrospective study

Background The age when pelvic-perineal injury patterns shift after child sexual abuse has not been formally identified, hindering development of age-specific examination protocols, especially in conflict zones with severe injuries and limited expertise. This study aimed to determine the association between age and pelvic-perineal trauma prevalence, identify the age threshold where injury patterns shift, and compare injury co-occurrence
before and after this threshold.
Methods Medical records of 5692 females <18 years treated for sexual assault at Panzi Hospital, Democratic Republic of Congo in 2003–2020 were analyzed. Six injury types (hymenal, perineal, vaginal, anal, rectal, Douglas pouch) were examined by age. Eight analytical methods identified age threshold without prior assumptions. Injury co-occurrence before and after this threshold was compared.
Findings Methods converged on 9–11 years; age 10 was selected and validated using menarche data (>98% of ≤10 group pre-menarcheal; 99.4% of >10 group post-menarcheal). All injuries except vaginal were more prevalent in the ≤10 group. Injury burden was higher prepubertally with 4–6 concurrent sites occurring in the ≤10 group (1.85 vs 1.18; d = 0.59). Network analysis showed anal injury was central prepubertally (EIF = +16.92) and vaginal injury central post-pubertally (+10.79). The perineal–anal association reversed from positive (+2.82) ≤ 10 to negative (−6.16) thereafter.
Interpretation Age 10 marks two distinct injury profiles. Prepubertal trauma is multifocal with an anal focus, whereas adolescent trauma centers on vaginal injury with sparser patterns. These findings support age-stratified examination protocols, including systematic ano-rectal assessment in prepubertal cases and vaginal-focused evaluation in adolescents.