Factors associated with poor fetal outcome in placental abruption

We aimed at describing placental abruption in our county and at evaluating factors associated with poor fetal outcome.

In this case-control study, women with placental abruption were identified from two databases of Brest University Hospital between January 2013 and December 2018.

Placental histological findings, course of pregnancies, maternal and fetal characteristics were described and compared between cases (placental abruption with stillbirth or neonatal death) and controls.

We identified 135 placental abruption, of whom 24.4% were complicated with stillbirth and 6.5% with neonatal death. Forty percent of women were smokers and 14.1% had a history of vasculoplacental disorder. Pregnancies were complicated with 42.2% of pre-eclampsia and 43% of intrauterine growth restriction. Cases were associated with more autoimmune diseases in mother (20.0% versus 3.2%, P = 0.003), more aspirin or heparin use during pregnancy (20.0% versus 6.3%, P = 0.03), less pre-eclampsia (25.0% versus 49.5%, P = 0.01) and more deliveries ≤ 34 weeks of gestation (80.0% versus 43.2%, P = 0.0001) than controls. Placentas from cases showed more placental indentation ≥ 30% (42.5% versus 5.3%, P < 0.0001) and less histological chronic inflammation, especially less chronic chorioamniotitis (2.5% versus 24.2%, P = 0.002) than controls. In multivariate analysis, factors negatively associated with poor fetal outcome were placental histological chronic inflammation (P = 0.01) and macroscopic infarcts (P = 0.01).

Poor fetal outcome is negatively associated with certain placental histological chronic lesions, but not with pre-eclampsia, what suggests various pathophysiological processes among placental abruption.