Impact of multiple placental pathologies on neonatal death, bronchopulmonary dysplasia, and neurodevelopmental impairment in preterm infants

Abstract

Background: To determine the association of placental pathology, including multiple placental lesions, with the occurrence and severity of bronchopulmonary dysplasia (BPD), death, and neurodevelopmental impairment (NDI) in preterm infants.

Method: A retrospective cohort study of neonates <29 weeks gestational age (GA) born at Parkland Hospital from 08/2009 to 08/2012. Infants were stratified as follows: Group 1: no significant placental pathology; Group 2: single significant placental lesion; and Group 3: ≥2 placental lesions (multiple lesions). Primary outcome was death and/or BPD. Two-year neurodevelopmental follow-up was compared.

Results: In all, 42% (100/241) of infants had one placental lesion, and 34% (82/241) ≥2 lesions. As the number of the pathologic lesions increased (no lesions vs. 1 vs. ≥2), the occurrence of death or BPD increased (25%, 37%, and 52%, respectively; P = 0.004). Moreover, infants with multiple pathologic lesions were more likely to have NDI (29%, 29%, and 46%, respectively; P = 0.03). After logistic regression, infants with multiple pathologic lesions were more likely to develop moderate-to-severe BPD [P < 0.01; OR 3.9 (1.5-10.1)] but not NDI.

Conclusion(s): Neonates <29 weeks GA with multiple placental pathologic lesions have an increased risk for developing BPD, suggesting an interaction between placental inflammation and vascular pathology and the pathogenesis of BPD; however, the risk of NDI is not increased.

Fig. 1

Flow diagram of the study population.

Fig. 2. Venn diagrams showing complexity of placental lesions (overlapping lesions).

MC chorioamnionitis without fetal vasculitis, FC chorioamnionitis with fetal vasculitis, MVU maternal vascular underperfusion, FTV fetal thrombotic vasculopathy, HGV high grade villitis, VE villous edema, SGA small for gestational age placenta, LGA large for gestational age placenta. The most common pathological lesion in the placentas in our patient population was histological acute chorioamnionitis (n = 119, 49%) and maternal vascular underperfusion (including SGA placentas) (n = 96, 40%). The most common complex placental pathological lesions (multiple lesions) were a combination of histological acute chorioamnionitis with LGA placentas (n = 30, 12%), followed by histological acute chorioamnionitis with SGA placentas (n = 15, 6%) and acute chorioamnionitis with MVU (n = 11, 5%). Chronic villitis and villous edema was seen in very small percentage of placentas (<5%).