The aim of the present study was to assess the association of prenatal exposure to hexachlorobenzene (HCB) and other organochlorine compounds with anthropometric measures at birth. A total of 98 mother-infant pairs (83% of all children born in a specific area polluted with HCB in the period 1997–1999) were recruited after giving written consent. Levels of organochlorine compounds were measured in 72 maternal serum samples at delivery and in 70 cord serum samples. Of the organochlorines measured in cord serum, median levels of HCB were higher than for the other compounds (median of HCB = 1.13 ng/mL, median of dichlorodiphenyl dichloroethylene = 0.85 ng/mL, and median of total polychlorinated biphenyls = 0.27 ng/mL). Premature newborns had higher concentrations of HCB [1.94 ng/mL among prematures versus 1.10 among nonprematures (p < 0.10)], dichlorodiphenyl dichloroethylene [2.40 versus 0.80 (p < 0.05)], and polychlorinated biphenyls in cord serum [0.70 versus 0.14 (p < 0.10)]. Those infants born with a small length for gestational age had higher levels of HCB in cord serum than those with an adequate length for gestational age [1.64 ng/mL versus 1.00 ng/mL (p < 0.05)]. In addition, HCB cord serum levels were negatively associated in a dose-response way with crown-heel length [for each doubling of the dose there was a decrease of 0.46 (SE = 0.22) cm] after adjusting for smoking, gestational age, and other organochlorine compounds. The associations of dichlorodiphenyl dichloroethylene and polychlorinated biphenyls with length were not significant. The results did not vary when stratified for prematurity. These data suggest that HCB reduces intrauterine physical linear growth.Abbreviations: HCB, hexachlorobenzene; p,p′-DDE, dichlorodiphenyl dichloroethylene; β-HCH, β-hexachlorocyclohexane; PCB, polychlorinated biphenyls