Correlation of Confined Placental Mosaicism with Fetal Intrauterine Growth Retardation

Objective: Our purpose was to determine if the frequency of confined placental mosaicism in newborns with unexplained intrauterine growth retardation (IUGR) was higher compared with infants with appropriate growth in utero and the outcome of these pregnancies. Study Design: A total of 20 cases with unexplained IUGR and 20 cases with appropriate growth for gestational age has been studied. Amnion, chorion and villi biopsy specimens were obtained from growth-retarded cases and controls at delivery. Cord blood specimens for 48-hour lymphocyte cultures were obtained from all infants with IUGR. Results: Karyotype analysis revealed confined placental mosaicism in two of 20 (10%) cases with IUGR. In one growth retarded case and one appropriate growth for gestational age case, mosaicism was also confirmed in the amnion. Cytogenetic analysis from peripheral blood of newborns showed normal karyotype in all cases. Three pregnancies in the group of fetuses with IUGR (15%) ended with fetal death compared with normal fetal surveillance of all cases from the control group. Conclusion: Confined placental mosaicism was detected two times more frequently from placentas of growth- retarded infants compared with those of newborns with appropriate growth. The fetal loss was significantly higher in the group of cases with IUGR compared with the control group.