Background: This study aimed to examine the associations between the urinary concentrations of phthalate metabolites among a sample of Iranian pregnant women with anthropometric measures of neonates.Methods: Urine samples were obtained from 121 pregnant women at their rst trimester of pregnancy; the levels of monobutyl phthalate (MBP), monobenzyl phthalate (MBzP), mono-2-ethylhexyl phthalate (MEHP), and mono (2-ethyl-5hydroxyhexyl) phthalate (MEHHP) metabolites were determined by gas chromatography mass spectrometry (GC/MS). The correlation between the urinary concentration of these metabolites and some sociodemographic factors of the participants (maternal education, age, family income, pre-pregnancy body mass index), their lifestyle variables (smoking habit, food pattern, and physical activity), cleaning products use data (cosmetic and household cleaning products) with anthropometric measures of neonates were investigated.Results: MBzP, MBP, MEHP, and MEHHP were detected in 100% of participants with the concentration ranged from 120 to 860 μg/g creatinine.Signi cant correlations were observed between the urinary levels of maternal MBzP (adjusted β =0.3 (0.001), p=0.03) and MEHHP and (adjusted β =0.3 (0.001), p=0.04) with the birth weight of female neonates. MBP (adjusted β = -0.3(0.02), p=0.04) and MBzP (adjusted β =-0.3 (0.001), p=0.02) were found negatively associated with head circumference in male and female newborns, respectively. Signi cant differences existed in the birth weight of infants whose mothers used plastic packaging for pickle and those who had history of passive smoking (p-value< 0.05).Conclusions: the studied metabolites had higher concentration in the Iranian pregnant women urine compared to the other countries. Higher levels of prenatal exposure to phthalate metabolites may adversely impact the health status of newborns.