Table 1: Clinical characteristics of the patients.

Group I: Down syndrome pregnancies
()
Group II: pregnancies without Down syndrome
()

Maternal age
(median ± SD)
37.14 ± 9.33533.21 ± 8.192
Number of pregnancies
(median ± SD)
1.143 ± 0.8991.214 ± 1.051
Gestational age at collecting of samples in weeks
(median ± SD)
15.77 ± 0.83416.64 ± 0.99

SD: standard deviation.