Single-twin demise: pregnancy outcome

Area of Science:

• Perinatology
• Maternal-Fetal Medicine
• Neonatology

Background:

• Single twin demise, or the loss of one twin in a multiple gestation, presents significant risks to the surviving co-twin.
• These risks include fetal loss, preterm birth, neurovascular injury, and end-organ damage.

Purpose of the Study:

• To review current research on the causes of single twin demise.
• To elucidate the pathophysiology of injury to the surviving co-twin.
• To evaluate evidence-based management strategies for these high-risk pregnancies.

Main Methods:

• Review of recently published research on single twin demise.
• Analysis of factors influencing co-twin risk, including gestational age at demise and chorionicity.
• Assessment of diagnostic and monitoring protocols, including ultrasound, Doppler studies, and MRI.

Main Results:

• Gestational age at demise and chorionicity are critical determinants of risk to the surviving twin.
• Recommended management includes fortnightly ultrasounds for growth, umbilical artery Doppler, and liquor volume assessment.
• Monochorionic twins require advanced Doppler assessment (e.g., middle cerebral artery velocimetry) and brain MRI at least 3 weeks post-demise to detect neurological morbidity.

Conclusions:

• Dichorionic pregnancies without other complications can proceed to term delivery.
• Monochorionic pregnancies require more intensive management, often with delivery between 34 and 36 weeks gestation.
• Close monitoring and tailored management strategies are essential for optimizing outcomes in surviving twins after single intrauterine fetal demise.