How can I counsel patients about the potential complications associated with placenta accreta spectrum during their antenatal visits?

When counseling patients about potential complications associated with placenta accreta spectrum (PAS) during antenatal visits, it is important to discuss several key aspects of diagnosis, management, and birth options ¹.

• Diagnosis and Referral: If a routine 20-week ultrasound scan shows placenta praevia or a low-lying placenta in a patient with a previous caesarean or uterine scar, they will be referred for a greyscale ultrasound scan with colour Doppler to assess for PAS ¹. This specialized scan should be performed around 28 weeks, but no later than 29 weeks, by a senior clinician with expertise in PAS diagnosis ¹. If PAS is suspected, the patient will be referred to a specialist placenta accreta spectrum centre for ongoing care and management ¹.
• Further Assessment: An MRI scan may be considered to complement ultrasound findings when planning surgical management of PAS ¹. Patients should be informed about what to expect during an MRI procedure and that it can help clarify the degree of invasion, especially with a posterior placenta ¹. It should also be discussed that current experience suggests MRI is safe, but there is a lack of evidence about any long-term risks to the baby ¹.
• Birth Options and Potential Complications: A senior obstetrician will discuss birth options with the patient, including the timing of birth and operative interventions ¹. This discussion will cover the possibility of a hysterectomy and the potential need for blood transfusion ¹. Patients should be aware that placental adherence problems, particularly after multiple caesarean births, are a relevant risk ¹. For planned caesarean birth in suspected PAS, a multidisciplinary team will be involved, including specialists such as gynaecological surgeons, interventional radiologists, colorectal surgeons, urologists, or vascular surgeons, depending on the nature of the PAS ¹. During a planned caesarean birth for a woman or pregnant person suspected to have PAS, a consultant obstetrician, a consultant gynaecologist, and a consultant anaesthetist will be present in the operating theatre ¹. A paediatric or neonatal registrar or consultant will also be present to provide immediate care for the baby ¹. A haematology registrar or consultant should be available for advice, and a critical care bed for the patient and a neonatal cot for the baby should be available ¹. Sufficient cross-matched blood and blood products will be readily available if blood transfusions are acceptable to the patient ¹.