In the context of the Duisburg Birth Cohort, this retrospective cohort study provides results of internal exposure to perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and perfluorohexanesulfonic acid (PFHxS) in 156 mother-child pairs, and investigates whether and to what extent in utero exposure of these chemicals at German background levels exerts an effect on newborn and infant weight and length, and weight in relation to length expressed by ponderal index, in order to examine whether any reduction in weight is disproportionate to length. The levels of PFOA, PFOS, and PFHxS were determined in 81 maternal and 83 umbilical cord stored frozen plasma samples and 105 umbilical cord blood samples. Calculated factors were used to convert umbilical cord values to maternal levels. Weights and lengths were retrieved at birth and at 1, 4, 6, and 12 mo from examination booklets and ponderal index (kg/m3) was calculated. Subsequently, correlations were assessed using multiple linear regressions and generalized estimation equations with each of the measures as a continuous outcome variable and with PFOA, PFOS, and PFHxS concentration quartiles as categorized predictor variables, while adjusting for relevant covariates. PFOA, PFOS, and PFHxS were generally within German background exposure levels. There was a significant association between PFOA, PFOS, and PFHxS concentration quartiles and decrease in ponderal index at birth but not weight or height. A nonsignificant negative association between exposure to all three compounds and birth weight was noted. Follow-up showed no sustained effect of the PFAA on anthropometric measures during the first year.