Placental pathology in relation to stillbirth and neonatal outcome in an extremely preterm population: a prospective cohort study.

OBJECTIVE

To study associations between placental histopathology and stillbirth as well as neonatal outcome in a population born extremely preterm.

DESIGN

Prospective cohort study.

SETTING

Stockholm, Sweden.

POPULATION: 167 infants born <27 gestational weeks during 2004-2007.

METHODS

One senior perinatal pathologist, blinded to outcome data, evaluated all placental slides.

MAIN OUTCOME MEASURES: Intrauterine fetal death, small-for-gestational age, major neonatal morbidity (intraventricular hemorrhage ≥grade 3, retinopathy of prematurity ≥grade 3, necrotizing enterocolitis, cystic periventricular leukomalacia or severe bronchopulmonary dysplasia) and neonatal mortality. Additional outcome variables were Apgar score at 5 min, sepsis, and treated patent ductus arteriosus.

RESULTS

Accelerated villous maturation was associated with a decreased risk for Apgar score <7 at 5 min (p = 0.041). Fetal thrombosis and low placental weight were associated with an increased risk for both intrauterine fetal death (p < 0.001 and p = 0.011, respectively) and small-for-gestational age (p < 0.001 and p < 0.001, respectively).

CONCLUSION

Placental histology may have prognostic value as it appears to be associated with intrauterine fetal death, as well as with being small-for-gestational age and assignment of a low Apgar score at birth.