Diagnostic Value of Preauricular Sulcus Morphology for Biological Sex Estimation and Obstetric History Reconstruction in a Documented Skeletal Collection from Cyprus

Abstract

The diagnostic value of the preauricular sulcus (PS) for biological sex estimation and obstetric history inference remains contested, partly because many skeletal investigations rely on archaeological samples without verified antemortem information. PS morphology was assessed in a modern, documented skeletal collection from Cyprus (n = 166; 124 males, 42 females; 14–80 years) using a three-tier ordinal scoring system (0: absent, 1: short/shallow, 2: wide/deep) based on macroscopic assessment of sulcus morphology. Verified antemortem data on biological sex, age, and parity were incorporated, and associations among PS score, biological sex, age, and parity were evaluated using Fisher’s exact test and Spearman’s rank correlation. Score 0 predominated in males (97.6%) and was also common among nulliparous females (73.3%); score 1 was infrequent in both sexes. In contrast, score 2 occurred exclusively in females and was present in all individuals with a documented history of at least one live birth, showing a strong positive association between PS score 2 and parity (rₛ = 0.912, p < 0.001). These results indicate that PS presence alone has limited diagnostic utility, whereas pronounced PS expression (wide/deep morphology) provides a high-specificity indicator of female sex and prior parturition in this documented skeletal sample from Cyprus. Grading sulcus intensity, rather than recording presence/absence, may improve the interpretive value of PS in forensic anthropological assessment.