**4. Time of delivery in monochorionic pregnancies**

The same review showed that monochorionic pregnancies beyond 34 weeks (13 studies, 2149 pregnancies), had a tendency for an increase in stillbirths compared to neonatal deaths after 36 weeks, with an additional 2.5 per 1000 perinatal deaths, which was not significant [8].

Just like DC gestations, there are no high-quality studies to respond with great certainty the right time for terminate monochorionic pregnancies. Most specialists in large reference centers recommend delivery of monochorionic/diamniotic twins between 36 + 0 and 36 + 6 weeks. This may be the point of balance between the already reduced risk of prematurity and the risk of fetal death [9].

There is still a lot of divergence between medical societies for the correct time of delivery. ACOG suggests delivery of monochorionic twins between 34 + 0 to 37 + 6 weeks of gestation [7] and the North American Fetal Therapy Network suggests delivery at 36 + 0 to 37 + 6 weeks of gestation [9]. However, others delegate delivery at 32 weeks of gestation [10]. It is clear that in cases of Twin-Twin Transfusion Syndrome, most of deliveries are performed earlier and this depends on the degree of complication that is present.

On the other hand, in monoamniotic pregnancies, most specialized centers in the world recommend delivery between 32 and 34 weeks. This fact is justified by the high rate of perinatal mortality in the third trimester (30–70%) and has as main motive the umbilical cords entanglement in the same amniotic chamber [4, 11, 12].
