rh sensitization can occur when a person with rh-negative blood is exposed to rh-positive blood. during pregnancy an rh-negative woman can become sensitized if she is carrying an rh-positive fetus. factors that increase the risk of blood mixing and sensitization during pregnancy include: 2 delivery. abdominal trauma such as from a car accident. abdominal surgery such as a cesarean section. placenta abruptio or placenta previa both of which can cause placental bleeding. external cephalic version for a breech fetus. obstetric procedures such as amniocentesis fetal blood sampling or chorionic villus sampling (cvs). miscarriage (spontaneous abortion ) ectopic pregnancy or elective abortion (medical or surgical abortion) after 8 weeks of fetal age (when fetal blood cell production begins). partial molar pregnancy involving fetal growth beyond 8 weeks. although rare rh sensitization has been known to occur after needle sharing between intravenous drug users. transfusing rh-positive blood in an rh-negative person can also trigger sensitization. but this is extremely rare because blood is always tested prior to transfusion. webmd medical reference from healthwise this information is not intended to replace the advice of a doctor. healthwise disclaims any liability for the decisions you make based on this information. © 1995-2011 healthwise incorporated. healthwise healthwise for every health decision and the healthwise logo are trademarks of healthwise incorporated.
what increases the risk of getting rh sensitization during pregnancy?