# Brain Injury and Neurodevelopmental Outcome in Survivors After Spontaneous Single Fetal Demise in Monochorionic Twins: A Systematic Review and Meta‐Analysis

## TL;DR

This study finds that one in four surviving monochorionic twins after a fetal demise experience brain injury, often linked to premature birth and exsanguination.

## Contribution

The study provides a meta-analysis of brain injury and neurodevelopmental outcomes in surviving monochorionic twins after fetal demise.

## Key findings

- Brain injury occurs in 27% of survivors after fetal demise in monochorionic twins.
- Neurodevelopmental impairment occurs in 6% of survivors, with higher rates among those with brain injury.
- Premature birth is associated with increased risk of brain injury in these cases.

## Abstract

Monochorionic (MC) twins are at risk of acute exsanguination after single fetal demise (sFD) due to their shared placental circulation, which may result in sequelae for survivors.

To evaluate the prevalence of ante‐ and postnatal brain injury and long‐term neurodevelopmental impairment (NDI) in co‐twins after sFD. Secondary outcomes were the prevalence of termination of pregnancy (TOP), neonatal death (NND) and potential risk factors for brain injury.

PubMed, Embase, Scopus and Web of Science were searched to identify relevant studies in October 2024.

Studies reporting MC twin pregnancies with spontaneous sFD. Studies with selective feticide, twin reversed arterial perfusion sequence, twin anaemia–polycythaemia sequence, congenital anomalies, higher‐order multiple pregnancies, fetoscopic laser surgery and double fetal demise were excluded.

Systematic review and meta‐analysis were performed following the PRISMA and MOOSE guidelines.

Thirteen studies involving 311 survivors after sFD were included. The prevalence of TOP, NND, brain injury and NDI was 3% (95% CI: 0%–7%), 6% (95% CI: 0%–16%), 27% (95% CI: 18%–37%), 6% (95% CI: 3%–11%), respectively. The median GA at birth in survivors with brain injury was 29 weeks (IQR 27.7–34.1) compared to 36 weeks (IQR: 32.3–37.0) in the overall group of survivors.

Brain injury occurs in one in four survivors and is associated with lower GA at birth, suggesting a double‐hit injury due to a combination of exsanguination and (severe) prematurity. NDI occurs in one in 20 survivors, compared to two‐thirds of those with brain injury.

PROSPERO number: CRD42024608912