Table 1 Demographic characteristics of the group.

Height [mean]

165 cm (SD = 13.33)

Weight [mean[

66 kg (SD = 7.88)

BMI [mean]

24.82 kg/m2 (SD = 4.13)

 PTL (< 37 weeks of gestation)

7.21% (n = 84)

 PTL (< 35 weeks of gestation)

2.57% (n = 30)

 Spontaneus PTL [% in cohort]

4.63% (n = 64)

 Spontaneus PTL [% in PTL patients]

76.20%

Previous preterm labour

1.55%(n = 18)

 IVF pregnancy

4.3% (n = 50)

 1st pregnancy

37.8% (n = 440)

 Pre-pregnancy diabetes

1.12% (n = 13)

 Pre-pregnancy hypertension

0.6% (n = 7)

 High risk for trisomy 21 (> 1:300)

7.98% (n = 93)

 Intermediate risk for trisomy 21 (1:301–1:1000)

14% (n = 163)

High risk for trisomy 18 (> 1:300)

0.68% (n = 8)

Intermediate risk for trisomy 18 (1:301–1:1000)

1.97% (n = 1164)

High risk for trisomy 13 (> 1:300)

0.51% (n = 6)

Intermediate risk for trisomy 13 (1:301–1:1000)

0.77% (n = 9)

PAPP-A < 0,4 MoM

3.78% (n = 44)