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Question 170
Delivery suite → Haemorrhage
Classification
Question
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An unsensitised RhD-negative woman at 33 weeks presents with painful APH and uterine tenderness. Ultrasound demonstrates no retroplacental collection. Kleihauer testing shows a significant fetomaternal haemorrhage. Which interpretation is most accurate?
Question Stem
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Options
A
The positive Kleihauer test confirms placental abruption
B
The result quantifies fetomaternal haemorrhage for anti-D dosing but does not establish the cause of the APH
C
The positive result compensates for the negative ultrasound and therefore establishes abruption
D
The result demonstrates that fetal compromise must be present
E
The result removes the need for clinical assessment of placental abruption
Explanation
The Kleihauer test and ultrasound answer different clinical questions, and neither should be misused diagnostically. In an RhD-negative woman, Kleihauer testing quantifies fetomaternal haemorrhage and assists calculation of additional anti-D requirements. It is not sufficiently sensitive or specific to diagnose placental abruption. Similarly, absence of a retroplacental collection on ultrasound does not exclude abruption. The diagnosis therefore remains clinical, integrating pain, bleeding, uterine findings and maternal and fetal condition.
Option Validity
A) A positive Kleihauer test demonstrates fetomaternal haemorrhage but does not confirm its obstetric cause.
C) Combining a positive Kleihauer result with a negative ultrasound does not create a diagnostic test for abruption.
D) Fetomaternal haemorrhage does not itself prove current fetal compromise.
E) Clinical assessment remains essential because abruption is principally a clinical diagnosis.
Further Reading
RCOG Green-top Guideline No. 63. Antepartum Haemorrhage. Royal College of Obstetricians and Gynaecologists; 2011.