Dichorionic triamniotic triplet pregnancy complicated by acardius acormus

Area of Science:

• Perinatology
• Reproductive Medicine
• Fetal Medicine

Background:

• Acardiac twinning is a rare complication of monochorionic pregnancies.
• The acormus phenotype, characterized by a well-developed cephalic pole but absent trunk and limbs, is particularly uncommon.
• Higher-order multiple gestations present unique challenges in managing twin-specific anomalies.

Observation:

• A triplet pregnancy was diagnosed with an acardiac fetus exhibiting the acormus phenotype at 15 weeks gestation.
• The co-fetus showed no signs of hydrops or heart failure, allowing for conservative management.
• The pregnancy progressed to preterm labor and delivery at 26+5 weeks.

Findings:

• This represents the first antenatal description of the acormus phenotype in a higher-order multiple pregnancy.
• The authors propose a potentially distinct pathophysiology for this rare acardiac phenotype compared to other types.
• Perinatal outcomes in triplet pregnancies with acardiac fetuses indicate delivery typically occurs between 26-27 weeks gestation.

Implications:

• This case highlights the importance of detailed prenatal ultrasound for diagnosing rare fetal anomalies.
• Understanding the pathophysiology of the acormus phenotype may inform future management strategies.
• Further research is needed to explore therapeutic interventions for acardiac twinning in multiple gestations.