Background <p>Maternal prenatal exposures to per- and polyfluoroalkyl substances (PFAS) have been linked to adverse birth outcomes. However, few investigations have considered paternal PFAS exposure. We estimated the parent-specific associations of prenatal PFAS exposures with adverse birth outcomes.</p> Methods <p>This study included 498 couples from the INUENDO cohort recruited at antenatal care visits in Greenland, Poland, and Ukraine during 2002–2004. We measured five major types of PFAS in parental serum during pregnancy. We analyzed three birth outcomes ascertained from medical records, including gestational age, birth weight, and birth length. We used weighted least squares linear regression to evaluate parent-specific associations of serum PFAS with the birth outcomes, adjusting for parental co-exposures and covariates. We also used quantile g-computation for mixture modeling of the birth outcomes of paternal and/or maternal exposures to multiple PFAS.</p> Results <p>No associations were found between maternal and paternal PFAS exposures and gestational age. However, after adjusting for paternal PFOA, a higher level of maternal serum perfluorooctanoate (PFOA) was linked to a tendency towards lower birth weight and shorter birth length. Paternal exposure to several PFAS was also associated with a tendency for shorter birth length, but the estimated effect sizes were small. We found no joint exposure effects in the mixture analyses.</p> Conclusions <p>While the evidence was inconclusive, maternal PFOA and paternal PFAS exposures seemed to be associated with lower offspring birth weight and shorter birth length, respectively. Parent-specific effects of PFAS exposures on offspring growth and development warrant further research.</p>