Report on products of conception (POC) samples with uniparental disomy (UPD) of a single chromosome, estimate the incidence of single UPD in miscarriage, and highlight single UPD cases associated with genetic conditions or placental insufficiency that may relate to the loss. Retrospective analysis of POC and maternal (mat) blood samples shipped to a lab for genotyping using Illumina CytoSNP-12b microarrays with informatics. Of 47,394 samples, 40,980 (86.5%) had fetal results: 113 (0.3%) had single UPD, including 29 (25.7%) with additional findings. 16 chromosomes had at least 1 case of single UPD (Table 1). The majority had heterozygous (htz) UPD (87, 77.0%). 38 cases (33.6%) involved chromosomes with a known phenotype due to imprinting or placental insufficiency (Table 1). The average mat age of single UPD cases was 35.5 years and the average gestational age was 62 days (range 35-240 days) vs. 36.8 years and 55 days (range 35–83 days) for cases with single UPD and aneuploidy. Four cases of single UPD miscarried past the first trimester, 3 involved chromosomes with known phenotypes. Single UPD of specific chromosomes is associated with pregnancy loss and/or genetic disease through imprinting defects, unmasking recessive alleles, and late trisomy rescue. This study identified 84 cases of single UPD without additional findings. 38 involved chromosomes known to cause an abnormal phenotype due to imprinting or placental insufficiency which may explain the loss. As 28 miscarriages had maternal UPD of chromosome 16, performing POC analysis that can identify UPD in miscarriages after diagnosis of intrauterine growth restriction is critical.