Introduction: Trisomy 18 and 13 are the most common autosomal trisomies, after trisomy 21, and their frequency is rising due to the increased maternal age of pregnant women. The fetuses suffer from multi-organ damage that may lead to many gestational complications as well as short life expectancy.
Objective: To assess the indications for prenatal karyotyping of trisomy 13 (T-13, Patau syndrome) and trisomy 18 (T-18, Edwards syndrome) during pregnancy in our medical center.
Methods: This retrospective cohort study involved all singleton pregnancies locally diagnosed or referred to our Institute because of T-13 and T-18, during the years 1998-2011.
Results: There were 1879 cases of termination of pregnancies (TOPs) because of fetal indications, of them 53 cases of T-18 and 10 cases of T-13. The main indications for prenatal karyotyping in our study group were abnormal sonographic findings during anomaLy scans. In addition, 7 newborns with T-18 and 3 infants with T-13 were born in our hospital during the same period of time. We examined all cases that led to the Live birth of newborns with chromosomal anomalies, stemming from the Lack of extraction of the tests mentioned above and/or ignoring findings that raise suspicion that requires performing prenatal karyotyping during pregnancy.
Discussion: Our findings corresponded with other studies and showed that prenatal diagnosis of T-13/T-18 due to abnormal sonographic finding is rising.
Conclusions: Our study shows that it was possible to identify the vast majority of T-13/T-18 among the pregnant women who had an increased risk based on a combination of the routine screening tests applied in Israel.