Sharing one foetal membrane, or chorion. Typically used of identical twins.(adjective)
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Use "monochorionic" in a sentence
"There is a higher complication rate in monochorionic (shared placenta) twin gestations as a result of the placental connections between the twins."
"Fetoscopic umbilical cord cauterization to prevent neurologic injury in monochorionic twins"
"Given that intrauterine death of one fetus in monochorionic twin pregnancies is associated with a 50-percent loss of the other twin, or a 40 to 60 percent incidence of significant neurologic injury if the other twin survives the death of its co-twin, the risks to the donor twin in this case for death or neurologic injury were high."