Piglet perinatal mortality is partly due to delayed maturation at the end of gestation. A fine balance of feto-maternal allocation of resources is necessary to support this process. Regulations result from interactions between maternal and fetal genes, maternal nutrition and the environment, as well as endometrial and placental functions. An experiment based on the use of mixed semen of two breeds with contrasting piglet maturity (i.e., Large White (LW) and Meishan (MS)) was performed. We investigated fetal genomeand sex influences on the expression of 41 imprinted genes from days 90-110 of gestation (D90-D110) at the level of the dam endometrium. Standardized relative expression data were quantified by qPCR and analyzed using linear mixed models (FDR<0.05).Correlations between endometrial gene expression and four fetal phenotypes (body weight and length, weight indexes) were analyzed. Comparison of LW and MS endometria showed a difference in the expression of 15 genes at D90 and five genes at D110.Gene expression was correlated more with fetal phenotypes at D90 than at D110. Particularly, a relation between fetal length and seven genes at D90 was highlighted. At D90, the fetal genome influenced expression of five genes in the LW endometrium supplyingfemale fetuses and two genes in the MS endometrium supplying male fetuses. Fetal sex influenced the expression of 11 genes in the endometrium associated with MS paternal genome fetuses. Our study provides new information about the contribution of the fetal genome and sex to feto-maternal interactions. The results suggest that the paternal genome, particularly in crossbreed production systems, contributes substantially to piglet survival