EMQ — Extended Matching Question · Review
Question 36
Feto-maternal medicine → Perinatology
Classification
Question
EEMQAnswer Bank
Correct Answer
Explanation
Maternal hepatitis B viral load is an important determinant when counselling about mother-to-child transmission in the context of invasive prenatal diagnosis. Transmission risk is low when the maternal viral load is below approximately 6.99 log10 copies/mL and increases at higher viral loads. Therefore the woman's blood-borne virus results, including viral load where relevant, should be reviewed and management individualised. Factors such as maternal parity, fetal sex, placental location and body mass index are not the principal viral determinant for this counselling decision.
Option Validity
A) Maternal age is not the principal hepatitis B transmission determinant described here.
B) Parity does not provide the relevant measure of hepatitis B infectivity.
C) Fetal sex is not the key determinant of hepatitis B vertical transmission risk.
D) Placental location is not the principal viral risk measure.
E) Previous mode of delivery does not quantify current hepatitis B infectivity.
F) Maternal body mass index is not the relevant viral transmission marker.
G) Number of previous pregnancies does not quantify hepatitis B transmission risk.
Further Reading
Navaratnam K, Alfirevic Z; Royal College of Obstetricians and Gynaecologists. Amniocentesis and chorionic villus sampling: Green-top Guideline No. 8. BJOG 2022;129:e1-e15. doi:10.1111/1471-0528.16821.