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. 2024 Nov;39(11):1267-1276.
doi: 10.1007/s10654-024-01171-z. Epub 2024 Nov 22.

Placental abruption and perinatal mortality in twins: novel insight into management at preterm versus term gestations

Rachel Lee  1 , Justin S Brandt  2 , Cande V Ananth  3   4   5   6
Affiliations

Placental abruption and perinatal mortality in twins: novel insight into management at preterm versus term gestations

Rachel Lee et al. Eur J Epidemiol. 2024 Nov.

Abstract

Twins suffer a disproportionately higher burden of adverse perinatal outcomes than singletons. However, the degree to which preterm delivery shapes the relationship between abruption and perinatal mortality in twins is unknown. Through causal mediation decomposition, we examine how preterm delivery mediates the effect of abruption on perinatal mortality among twins using the US-matched multiple birth data (1995-2000). We estimated the hazard ratio (HR) from Cox models with gestational age as the timescale. We decomposed the total effect (TE) into counterfactual natural direct (NDE) and natural indirect (NIE) effects. 557,220 matched twin births, 1.3% (n = 7032) resulted in abruption with higher perinatal mortality rates than non-abruption births (143 versus 36 per 1000 births, respectively) and a 4.53-fold (95% confidence interval [CI]: 4.23, 4.82) increased hazard of perinatal mortality. HRs for NDE and NIE were 3.05 (95% CI: 2.84, 3.24) and 1.49 (95% CI: 1.49, 1.47, 1.50), respectively, and the proportion mediated (PM) was 41%. PM increased as the gestational age at delivery decreased. Associations persisted after correction for unmeasured confounders. The best strategies to improve perinatal delivery are delivery when abruption complicates twin pregnancies at term gestations and expectant management (avoiding early preterm delivery), if feasible, when abruption complicates twin pregnancies at preterm gestations.

Keywords: Causal mediation analysis; Perinatal mortality; Placental abruption; Preterm delivery.

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Conflict of interest statement

Declarations. Ethical approval: No ethics approval was required since the data used in this study was available in de-identified form. Competing interests: None declared.

Figures

Fig. 1
Fig. 1
Simplified directed acyclic graph showing the relationship between placental abruption and perinatal mortality with preterm delivery as the mediator: US Matched Multiple Birth File, 1995–2000
Fig. 2
Fig. 2
Perinatal mortality rates (per 1000 twin births) among non-abruption and placental abruption births and hazard ratio of mortality by gestational age, US Matched Multiple Birth File, 1995–2000
Fig. 3
Fig. 3
Kaplan-Meier curve showing the probability of perinatal survival among abruption and non-abruption births by gestational age: US Matched Multiple Birth File, 1995–2000
Fig. 4
Fig. 4
Decomposed effects of preterm delivery on abruption and perinatal mortality association: US Matched Multiple Birth File, 1995–2000
See this image and copyright information in PMC

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References

    1. Brandt JS, Ananth CV. Placental abruption at near-term and term gestations: pathophysiology, epidemiology, diagnosis, and management. Am J Obstet Gynecol. 2023;228(5S):S1313–29. - PMC - PubMed
    1. Ananth CV, et al. Placental abruption and adverse perinatal outcomes. JAMA. 1999;282(17):1646–51. - PubMed
    1. Ananth CV, Wilcox AJ. Placental abruption and perinatal mortality in the United States. Am J Epidemiol. 2001;153(4):332–7. - PubMed
    1. Ananth CV, et al. Placental abruption among singleton and twin births in the United States: risk factor profiles. Am J Epidemiol. 2001;153(8):771–8. - PubMed
    1. Martin JA, Hamilton BE, Osterman MJ. Three decades of twin births in the United States, 1980–2009. NCHS Data Brief. 2012(80):1–8. - PubMed

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