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Abstract
Morbidly adherent placenta (MAP) is the abnormal attachment of the placenta to the uterine wall in which trophoblastic cells invade the uterine tissues. MAP is rare, affecting 1 in 2500 pregnancies1, however it is associated with high feto-maternal morbidity and mortality2. Previous caesarean section is a major risk factor for development of MAP3, and complicates 24% of cases of placenta praevia after one prior caesarean section4. With the current trend of increasing caesarean section rates5, MAP will pose significant obstetric problems in the future.
Antenatal diagnosis of MAP has been shown to reduce maternal morbidity6. Recent guidance from the National Institute for Clinical Excellence suggests that in cases where there is suspicion of MAP, colour-flow Doppler ultrasound should be used as a first line diagnostic tool7. Presence of irregular lacunae within the placental architecture and loss of the clear space in the retroplacental plane are considered to be useful diagnostic criteria in ultrasound imaging of MAP8. Where such ultrasound changes are found, magnetic resonance imaging (MRI) can then be considered to confirm diagnosis and evaluate the extent of invasion which would aid management planning6.
We present a case series of 6 patients presenting to York Teaching Hospital in whom MAP was queried on the basis of previous caesarean section, placental localisation scan or clinical presentation. We discuss the role of colour-flow Doppler ultrasound in the initial assessment of suspected MAP followed by selective use of MRI.
References
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