RESUMO
The aim of the study was to compare perinatal outcome of singleton and twin pregnancies conceived after assisted reproductive technologies (ART). This retrospective study included singleton and twin pregnancies conceived after ART in the period from January 1, 2007 until December 31, 2008. The study variables were maternal age (years), parity, body mass index (BMI; kg/m2), week (< or =36 (6/7) and > or = 37) and mode of delivery (vaginal and cesarean section), birth weight (grams) and APGAR score (< or = 7; 8-10). During the study period, there were 195 pregnancies after ART that fulfilled inclusion criteria. We found no between-group difference in parity (chi2 = 0.0133; P = 0.9081), but such difference was found in mean age (t = 2.0486; P = 0.0419) and BMI (chi2 = 31.038; P = 0.001). A statistically significant difference was recorded in preterm delivery rate (chi2 = 25.539; P = 0.001), average duration of pregnancy (t = 12.8591; P = 0.001), average birth weight (t = 10.5446; P = 0.001) and mode of delivery (chi2 = 13,691; P = 0.001). A statistically significant difference was found in low birth weight babies (chi2 = 102.02; P = 0.001) and APGAR score (chi2 = 19.96; P = 0.001), but there was no difference in the prevalence of small for gestational age babies (chi2 = 0.90629; P = 0.635). In conclusion, this study indicated the perinatal outcome after ART to be considerably poorer in twins than in singletons.