monocchoriondiamniónico

Monochorionic diamniotic pregnancy refers to a type of twin pregnancy where both fetuses share a single placenta but have their own individual amniotic sacs. This occurs when a fertilized egg splits into two embryos after the formation of the chorion, the outer membrane of the developing placenta, but before the formation of the amnion, the inner membrane that encloses the amniotic fluid. This splitting typically happens between days 7 and 12 after fertilization. Monochorionic diamniotic pregnancies are the most common type of twin pregnancy, accounting for approximately 70-75% of all twin gestations.

While sharing a single placenta can facilitate nutrient and oxygen exchange between the fetuses, it also carries specific risks. The fused placental circulation can lead to vascular connections between the twins, which may result in complications such as twin-to-twin transfusion syndrome (TTTS), where one twin receives too much blood flow and the other receives too little. Other potential issues include selective intrauterine growth restriction, discordant fetal anomalies, and increased risk of preterm birth. Regular monitoring through ultrasound is crucial for identifying and managing these potential complications. The diamniotic nature means that each twin has its own sac of amniotic fluid, which is essential for fetal development and movement.