Placental pathology in perinatal asphyxia: a case-control study.

Area of Science:

• Perinatal pathology
• Neonatal neurology

Background:

• Birth asphyxia and hypoxic-ischemic encephalopathy (HIE) are significant concerns in neonatology.
• Previous studies suggested associations between placental lesions (maternal vascular malperfusion - MVM, fetal vascular malperfusion - FVM, chorioamnionitis with fetal response - FIR) and birth asphyxia.

Purpose of the Study:

• To compare placental pathology in asphyxiated newborns, including those with HIE, against non-asphyxiated controls.
• To investigate the association between clinical risk factors and placental findings in neonatal asphyxia.

Main Methods:

• A retrospective case-control study analyzed placentas from neonates (gestational age ≥ 35 weeks, birthweight ≥ 1,800 g, no malformations).
• Cases included asphyxiated newborns (pH ≤ 7.0 or base excess ≤ -12 mMol, 10-minute Apgar score ≤ 5, or prolonged resuscitation), with or without HIE.
• Controls were non-asphyxiated newborns from low- or high-risk pregnancies, with placental analysis following the Amsterdam Placental Workshop Group Consensus Statement 2014.

Main Results:

• Asphyxiated newborns had higher rates of nulliparity, BMI>25, thick meconium, abnormal fetal heart monitoring, and acute intrapartum events.
• Contrary to expectations, MVM and FVM were more frequent in non-asphyxiated controls than in asphyxiated cases (p<0.001).
• Histologic meconium-associated changes (MAC) were exclusively observed in asphyxiated newborns (p=0.039), with no significant differences in inflammatory lesions or umbilical insertion site abnormalities.

Conclusions:

• Antepartum and intrapartum risk factors play a confirmed role in neonatal asphyxia and HIE.
• Neonatal asphyxia showed no significant association with common placental lesions (MVM, FVM), except for MAC.
• Understanding the interplay between clinical data and placental findings is vital for preventing perinatal asphyxia.