One of these rare studies is the study by Pedersen et al.(26)in 1995, according to this study, there was no difference between serum levels of human placental lactogen (hPL), PAPP-A, and endometrial secretory protein PP14 (PP14) in 29 women with and 40 women with subchorionic hemorrhage, and there was no correlation between serum levels and hematoma size. The gene discussed is PAPPA; the disease is hematoma.