Interest of the Kleihauer in Patients With Decreased Active Fetal Movements

Fetomaternal hemorrhage is the passage of fetal red blood cells through the placental barrier into the maternal blood. This phenomenon frequently occurs in the third trimester for small quantities of blood \< 0.5 ml and is without fetal consequences in rhesus positive patients. This hemorrhage can sometimes be more important and be the cause of fetal anemia or even fetal death in utero. Diagnostic confirmation is biological and is performed using the Kleihauer test. It is based on the identification by the biologist of fetal cells circulating in the maternal blood by counting acid-fast fetal cells under the microscope. It is therefore a time-consuming examination with significant inter- and intra-observer variability. The clinical sign most often reported in the literature, and the earliest sign that may suggest fetomaternal hemorrhage complicated by fetal anemia, is a decrease in active fetal movements. However, this is an aspecific sign and is one of the most common reasons for consultation in obstetric emergencies.