Home Products Most Popular Contact
No items in your cart.
The page below is a sample from the LabCE course Hemolytic Disease of the Fetus and Newborn. Access the complete course and earn ASCLS P.A.C.E.-approved continuing education credits by subscribing online.

Learn more about Hemolytic Disease of the Fetus and Newborn (online CE course) »
How to Subscribe
MLS & MLT Comprehensive CE Package
Includes 129 CE courses, most popular
$95 Add to cart
Pick Your Courses
Up to 8 CE hours
$50 Add to cart
Individual course$20 Add to cart

Factors That Affect Production of Anti-D

Exposure to D+ red cells: Anti-D is red cell immune. The usual route of exposure to the D antigen is during pregnancy. Fetal bleeds into the mother occur more commonly at delivery but some may occur antenatally due to small lesions in the placenta or due to placenta previa, amniocentesis, abdominal trauma, abortion, ectopic pregnancy, etc.
Transfusion is a relatively rare route of exposure since Rh-negative individuals normally receive only Rh-negative donor red cells. However, Rh-negative transfusion recipients may be exposed to small volumes of D-positive red cells in Rh-positive platelet concentrates. Also, there are rare reports of fresh frozen plasma, not normally matched for Rh(D), causing anti-D production.
Volume of fetal bleed: In general, the larger the fetal bleed, the more likely the mother is to produce anti-D. Approximately 1 pregnancy in 400 results in a fetomaternal hemorrhage (FMH) of 30 mL or greater.
ABO incompatibility between mother and fetus: If fetal red cells are ABO incompatible with the mother, maternal anti-A or anti-B will rapidly remove fetal cells from the circulation before anti-D can be produced. This protection decreases the chance of anti-D being produced but does not eliminate it entirely.