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Question 166
Delivery suite → Haemorrhage
Classification
Question
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An unsensitised RhD-negative woman has recurrent APH at 29, 31 and 33 weeks. She received anti-D after the first episode. Following the third episode, a colleague argues that no further prophylactic assessment is necessary because all three bleeds probably arise from the same placental pathology. Which principle is most appropriate?
Question Stem
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Options
A
Anti-D is required only for the first APH occurring in any pregnancy
B
Recurrent APH should be managed as potentially repeated sensitising exposure, with anti-D prophylaxis and assessment according to gestation, timing and fetomaternal haemorrhage
C
Anti-D should be withheld once placental abruption has been clinically suspected
D
Kleihauer testing can replace anti-D prophylaxis when recurrent bleeding occurs
E
Anti-D is unnecessary if fetal monitoring remains reassuring
Explanation
Recurrent APH in an unsensitised RhD-negative woman creates continuing or repeated potential exposure to fetal RhD-positive cells. Previous administration of anti-D does not justify assuming that all later bleeding is already covered indefinitely. Further prophylaxis should therefore be considered according to the timing and gestation of recurrent sensitising events, with assessment of fetomaternal haemorrhage where indicated to determine whether additional anti-D is required. Neither fetal wellbeing nor the presumed placental cause determines whether maternal sensitisation can occur.
Option Validity
A) A previous dose does not necessarily provide adequate prophylaxis for all subsequent sensitising episodes.
C) Suspected placental abruption does not remove the indication for appropriate RhD prophylaxis.
D) Kleihauer testing quantifies fetomaternal haemorrhage; it does not itself provide immunoprophylaxis.
E) A reassuring fetal heart rate does not determine the risk of maternal RhD sensitisation.
Further Reading
RCOG Green-top Guideline No. 63. Antepartum Haemorrhage. Royal College of Obstetricians and Gynaecologists; 2011.