Anti-D Prophylaxis Flashcards
What is the rationale for routine antenatal anti-D prophylaxis?
Majority of Rh negative mothers become sensitized due to “silent” sensitization secondary to occult FMH mostly after 28 weeks of pregnancy.
RAADP given to protect against and prevent this.
What are the recommendations for RAADP?
NOT DONE IN SRI LANKA
Offer to all non-sensitized Rh negative mothers at 28 weeks.
Do not offer to already sensitized mothers.
Take an antibody screening sample before giving anti-D.
Give RAADP even if anti-D given before 28 weeks.
Give additional anti-D if sensitizing event occurs after RAADP
What are the instances where Rh negative mother’s blood group antibodies are screened?
Booking visit (send to NBTS)
28 weeks before RAADP
Results come back to the clinic
How do you calculate the dose of anti-D?
RAADP 1500 IU at 28 weeks given in Sri Lanka
Can also give 500 IU each at 28 and 34 weeks
125 IU per mL of FMH
After delivery if baby is Rh positive —>
Calculate volume of FMH using Kleihauer test done within 2 hours of delivery
99% have <4 mL of FMH at delivery. Therefore give 500 IU
What are the instances where there is likely to be more than 4 mL of FMH?
LSCS Traumatic delivery Stillbirth IUD Multiple pregnancy Manual removal of placenta Abdominal trauma in T3 Unexplained hydrops fetalis
Give standard 1500 IU anti-D if baby is Rh positive
What are the indications for non-routine anti-D prophylaxis?
Spontaneous MC after 12+0
Spontaneous MC before 12+0 with instrumentation/curettage
Curettage at any POA
Medical ERPC at any POA
Threatened MC after 12+0
Surgical or medical TOP at any POA
All ectopic pregnancies
Antenatal events (invasive prenatal diagnosis, IU procedures, APH, IUD, ECV, any abdominal trauma)
How and when do you give anti-D?
ASAP within 72 hours of FMH event, but can give even up to 10 days after.
Intramuscular to deltoid
Subcut or IV if bleeding diathesis
