Outcomes in prenatally suspected focal placenta accreta spectrum

Morbidity of placenta accreta spectrum (PAS) increases with increasing severity of placental attachment. PAS with only a focal area of invasion or focal PAS based on magnetic resonance imaging (MRI) has been defined in a previous study as the greatest dimension of involvement of 25 mm or less. The objective of this study was to describe maternal and neonatal outcomes in patients with prenatally suspected focal PAS as defined by MRI imaging.

This is a retrospective cohort study evaluating prenatally suspected focal PAS between 2020 and 2024. Focal PAS was defined based on MRI. Delivery and neonatal outcomes were described for the entire cohort and these outcomes were then compared between patients who delivered at <37 weeks (preterm) or at ≥37 weeks (term). A neonatal composite of cord pH < 7, cord base excess <-12, APGARs ≤3, continuous positive airway pressure/ventilator support, hypoxic ischemic encephalopathy, birthweight <3rd percentile, neonatal intensive care unit admission (NICU), and hypoglycemia was compared.

Of 40 cases of prenatally suspected focal PAS, 21 (52%) cases delivered preterm and 19 (48%) delivered at term. Six (15%) met International Federation of Gynecology and Obstetrics (FIGO) clinical criteria for PAS. Hysterectomy was performed in 3 (8%) cases. Pathology was negative in 33 (85%) patients, not sent in 1 patient, and positive for PAS in 6. The neonatal composite occurred in 11 (28%) neonates. Median APGARs at 1 min were 6 (6-8), no neonate had a pH < 7, and median birthweight was 2905 g (2721-3108 g). Ten (25%) infants were admitted to the NICU. Patients delivered preterm were more likely to have a placenta previa (76% vs. 42%, p = 0.0115) and were more likely to stay for more than 3 days in the hospital (24% vs. 0%, p = 0.049). Neonatal length of stay was longer (6 [4-14] vs. 4 [4-4] days, p = 0.003), and the rate of the neonatal composite outcome was higher in patients delivered preterm (43% vs. 11%, p = 0.034).

Delivery and neonatal outcomes were favorable in cases of prenatally suspected focal PAS with low overall hysterectomy rates. Term delivery did not impact maternal outcomes, improved neonatal outcomes, and can be considered in an otherwise uncomplicated patient.