General median

<34 w

n = 6

34 - 37 w

n = 19

≥37 w

n = 117

P entre faixas de idade

Cervical Length

First trimester

36.5 ± 8.5

32.7 ± 13.0

38.2 ± 8.0

38.8 ± 4.5

0.056

Second trimester

35.3 ± 9.6

29.3 ± 15.2^a

38.8 ± 9.4^b

37.8 ± 4.9^b

0.008

P between trimesters

0.461

0.658

0.061