['We hypothesized that parenteral nutrition associated cholestasis (PNAC) would be more severe in small for gestational age (SGA) compared with appropriate for gestational age (AGA) very low birth weight (VLBW) infants.', 'Sixty-one VLBW infants were diagnosed as PNAC with exposure to parenteral nutrition with elevation of direct bilirubin≥2 mg/dL for ≥14 days. Twenty-one SGA infants and 40 AGA infants matched for gestation were compared.', 'Compared with AGA infants, PNAC in SGA infants was diagnosed earlier (25±7 days vs. 35±14 days, p=0.002) and persisted longer (62±36 days vs. 46±27 days, p=0.048). Severe PNAC, defined as persistent elevation of direct bilirubin≥4 mg/dL for more than 1 month with elevation of liver enzymes, was more frequent in SGA than in AGA infants (61% vs. 35%, p=0.018). The serum total bilirubin and direct bilirubin levels during the 13 weeks of life were significantly different in SGA compared with AGA infants. SGA infants had more frequent (76% vs. 50%, p=0.046), and persistent elevation of alanine aminotransferase.'] Is parenteral nutrition associated cholestasis earlier , more prolonged and severe in small for gestational age compared with appropriate for gestational age very low birth weight infants?