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Question 191
Delivery suite → Haemorrhage
Classification
Question
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A 41-year-old nulliparous woman with a dichorionic twin pregnancy conceived following assisted reproduction presents with painless APH at 29 weeks. She has no previous uterine surgery. Which reasoning most appropriately interprets her background risk for placenta praevia?
Question Stem
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Options
A
Nulliparity effectively removes the risk because previous uterine pregnancy is required for placenta praevia
B
Absence of previous caesarean birth makes placenta praevia sufficiently unlikely that placental location need not be established
C
Her age, multiple pregnancy and assisted conception are recognised associations, so the absence of a uterine scar does not remove the possibility of placenta praevia
D
Assisted conception is relevant only to placental abruption and not placenta praevia
E
Multiple pregnancy reduces the likelihood of placenta praevia because implantation occurs at more than one site
Explanation
Previous caesarean birth is an important risk factor for placenta praevia, but it is not a prerequisite. Advanced maternal age, multiple pregnancy and assisted conception are also recognised associations. This woman therefore has several relevant risk factors despite being nulliparous and having no uterine scar. In a woman presenting with painless APH, placental location must be established rather than allowing the absence of the classic previous-caesarean history to produce false reassurance.
Option Validity
A) Placenta praevia can occur in a nulliparous woman.
B) Absence of previous caesarean birth does not exclude placenta praevia.
D) Assisted conception is recognised among the associations with placenta praevia.
E) Multiple pregnancy is associated with increased rather than reduced risk of placenta praevia.
Further Reading
RCOG Green-top Guideline No. 63. Antepartum Haemorrhage. Royal College of Obstetricians and Gynaecologists; 2011.