LAUSR

Transplacental fetal cell transfer results in the engraftment of fetal‐origin cells in the pregnant woman's body, a phenomenon termed fetal microchimerism. Increased fetal microchimerism measured decades postpartum is implicated in maternal inflammatory disease. Understanding which factors cause increased fetal microchimerism is therefore important. During pregnancy, circulating fetal microchimerism and placental dysfunction increase with increasing gestational age, particularly towards term. Placental dysfunction is reflected by changes in circulating placenta‐associated markers, specifically placental growth factor (PlGF), decreased by several 100 pg/mL, soluble fms‐like tyrosine kinase‐1 (sFlt‐1), increased by several 1000 pg/mL, and the sFlt‐1/PlGF ratio, increased by several 10 (pg/mL)/(pg/mL). We investigated whether such alterations in placenta‐associated markers correlate with an increase in circulating fetal‐origin cells.