OBJECTIVE: To evaluate the the effect of chorionicity on maternal and neonatal results. METHODS: We examined the twin pregnancy cases who gave birth in our clinic between January 2002 and December 2006 retrospectively according to their chorionicities. Chorionicity was determined according to the ultrasonographic examination of the amnion and chorion in the first trimester, by the examination of the fetal gender or the observation of separate placental masses in the second and third trimesters, and via examination of the placenta after birth. The effect of chorionicity on neonatal and maternal results have been investigated. RESULTS: 90702 live births were documented in our clinic. 893 twin pregnancies have been observed among total cases. 678 of the twin pregnancies were incorparated into the study and 577 (%85.1) were dichorionic, 101 cases (%14.9) were monochorionic. Maternal age was significantly more higher in dichorionic twin pregnancies (p=0.008). Neonatal morbidity was significantly more common in monochorionic twin pregnancies (p=0,001). No significant difference was found in maternal morbidity between the case groups (p=0,45). Most common cause of maternal morbidity was preeclampsia and it was more frequent among the monochorionic cases (p CONCLUSION: Chorionicity affects neonatal and maternal morbidity in twin pregnancies. Therefore in twin pregnancies chorionicity must be determined especially in the first trimester.
Keywords: chorionicity, maternal morbidity, neonatal morbidity and mortality, twin pregnancy