Prevention of RhD alloimmunization in the first trimester of pregnancy: Clinical practice guidelines of the French College of Obstetricians and Gynecologists.

The French College of Obstetricians and Gynecologists has decided to update its clinical practices guidelines for preventing RhD alloimmunization in the first trimester of pregnancy. The quality of evidence of the literature was assessed following the GRADE methodology with questions formulated in the Patients, Intervention, Comparison, Outcome (PICO) format and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed using Pubmed, Cochrane, EMBASE, and Google Scholar databases. The quality of evidence was assessed (high, moderate, low, very low) and a recommendation was formulated: strong, weak, or no recommendation. The recommendations were reviewed in two rounds by members of the scientific board of the French College of Obstetricians and Gynecologists (Delphi survey) in order to select the consensus recommendations. The three recommendations from the PICO questions were agreed upon through the use of the Delphi method. It is not recommended to administer RhD immune globulin before 12 weeks of gestation to reduce the risk of alloimmunization in the event of induced or spontaneous abortion in RhD-negative patients when the progenitor is RhD-positive or unknown (weak recommendation, very low-quality evidence). It is not recommended to administer RhD immune globulin before 12 weeks of gestation to reduce the risk of alloimmunization in the event of bleeding (weak recommendation, very low-quality evidence). The quality and quantity of literature data are insufficient to determine whether injection of RhD immune globulin can reduce the risk of alloimmunization in ectopic pregnancy, so no recommendation could be made.