Delivery timing of placenta accreta spectrum: later is feasible

Delivery at 34 0/7 to 35 6/7 weeks of gestation is recommended for patients with prenatally suspected placenta accreta spectrum. However, data supporting these recommendations are limited. As a large-volume tertiary care center, in an otherwise uncomplicated pregnancy with prenatal concerns for placenta accreta spectrum, we have historically planned delivery at 36 0/7 to 37 6/7 weeks of gestation.

This study aimed to describe the effect of delayed delivery on maternal and fetal outcomes in patients with suspected placenta accreta spectrum.

This study examined pregnancies at ≥24 0/7 weeks of gestation complicated by prenatally suspected placenta accreta spectrum from August 2009 to April 2022. Maternal and neonatal outcomes were compared according to delivery timing (beyond 36 0/7 weeks vs prior to this gestational age). In addition, the indication for early delivery was determined. Statistical analysis used the χ² test for categorical variables and the Student t test for continuous variables.

Of 202 patients with prenatal concerns for placenta accreta spectrum, 65 (32%) had an early indication for delivery (bleeding, preeclampsia, premature rupture of membranes, or labor), whereas 137 (68%) had planned deliveries after 36 0/7 weeks of gestation for concern for placenta accreta spectrum. There was no difference in maternal age, race/ethnicity, parity, body mass index, or number of previous cesarean deliveries. The median gestational ages at delivery were 35 weeks (interquartile range, 31-36) in the indicated group and 37 weeks (interquartile range, 36-37) in the group without complications (P<.001). The prenatally suspected severity of placenta accreta spectrum did not differ between the groups or on pathology. Of the patients who delivered for indications, 42 (65%) delivered for bleeding, 11 (17%) delivered for labor, and 12 (18%) delivered for other indications. The only maternal outcome with a noted difference between the groups was increased whole blood transfusions (more commonly used at our institution in emergent situations) in patients with indicated deliveries (0 [interquartile range, 0-6] in the group with indications vs 0 [interquartile range, 0-4] in the group without indications; P=.007) and decreased platelet transfusions (0 [interquartile range, 0-6] in the group with indications vs 0 [interquartile range, 0-10] in the group without indications; P=.021). Neonates in the indicated cohort were more likely to have lower birthweights, neonatal intensive care unit admission, respiratory distress syndrome, need for mechanical ventilation, and longer hospital stays, all of which were likely secondary to prematurity.

Patients with suspected placenta accreta spectrum without other indications for delivery, such as bleeding, labor, rupture of membranes, or preeclampsia, can have a planned delivery in the late preterm or early term period at specialized centers that are geographically in close proximity to the patient. Later delivery does not affect maternal outcomes but improves neonatal outcomes.