Table 2 Pregnancy characteristics. Data are n (%) or median (range)

Gestational age at diagnosis (weeks)

21.8

(18.0–29.8)

23.0

(19.9–34.3)

22.9

(18.0–34.3)

0.093

Vasa previa type

0.256

 I

3 (25.0)

6 (15.8)

9 (18.0)

 II

3 (25.0)

20 (52.6)

23 (46.0)

 III

6 (50.0)

12 (31.6)

18 (36.0)

Cervical length (cm)

4.1 (3.3–6.0)

4.0 (2.1–5.8)

4.0 (2.1–6.0)

0.856

Placenta previa at initial diagnosis

4 (33.3)

17 (44.7)

21 (42.0)

0.526

Placenta previa resolved^a

1 (25.0)

8 (47.1)

9 (42.9)

0.603

Low-lying placenta

3 (25.0)

11 (29.0)

14 (28.0)

1.000

Succenturiate placenta

3 (25.0)

20 (52.6)

23 (46.0)

0.112

Fetal growth restriction

1.000

 No

12 (100)

36 (94.7)

48 (96.0)

 Yes

0 (0.0)

1 (2.6)

1 (2.0)

 No data

0 (0.0)

1 (2.6)

1 (2.0)

Gestational age at vasa previa resolution (weeks)

30.3 (24.9–34.2)

N/A

-

-

Interval from diagnosis to resolution (weeks)

7.9 (4.3–15.6)

N/A

-

-

Gestational age at delivery (weeks)

37.8 (32.2–41.0)

34.0 (28.0–36.6)

34.2 (28.0–41.0)

 < 0.001

Mode of delivery

 < 0.001

 Vaginal

5 (41.7)

0 (0.0)

5 (10.0)

 Cesarean

7 (58.3)

38 (100)

45 (90.0)

Birthweight (g)

3093

(1688–3790)

2294

(968–3340)

2441.5

(968–3790)

 < 0.001

NICU^b admission

3 (25.0)

30 (79.0)

33 (66.0)

0.001