Early embryo loss in dairy cattle is a major economic cost to dairy producers. A dairy operation with a low herd conception rate must use more feed and resources to be as productive as a herd with a higher conception rate and shorter calving interval. Our overall hypothesis is that a portion of these early embryo losses are mediated by aberrant response of the uterine immune system to the embryo. This research seeks to improve our knowledge of a potential cellular mechanism that may be involved in maintaining pregnancy, the aryl hydrocarbon receptor (AhR). The AhR is a ligand activated transcription factor involved in differentiation of T regulatory cells (T reg). We hypothesize that activation of T reg by AhR causes suppression of the maternal immune response to the allogeneic embryo. Holstein dairy heifers (n = 22) were estrous synchronized and bred by artificial insemination (Day = 0) or remained cyclic. Uterine endometrium was collected from heifers on Day 17 of the estrous cycle (n = 9), and Days 17 (n = 9) and 20 (n = 4) of pregnancy. Total cellular RNA was isolated from endometrial tissue using Trizol. The RNA was converted to cDNA and subjected to PCR using primers designed to recognize the bovine AhR. A single amplicon was visualized by gel electrophoresis and the DNA was excised, purified, and sequenced to confirm its identity. Purified cDNA from the amplicon was used to create a standard curve and a qPCR assay was developed and validated with a slope of −3.5 and efficiency of 93%. Analysis of steady-state mRNA abundance for AhR was conducted using RPL19 as the reference gene. Critical threshold (Ct) data were adjusted for RPL19 and 2^-ΔCt values were analyzed using PROC Mixed and orthogonal contrasts. Although AhR was abundantly expressed in the endometrium, there was no difference in AhR mRNA abundance between pregnant and nonpregnant heifers nor between d 17 and d 20 pregnant heifers (P > 0.1). Studies are ongoing to localize the AhR in endometrial tissue using immunofluorescence analysis. This study confirms the presence of the AhR gene in the bovine endometrium during the estrous cycle and early pregnancy.