Table 6 Characteristics of newborns admitted to NICU (N = 2746)

25(OH)D levels (Mean ± SD)

43.283 ± 15.893

42.319 ± 15.183

−2.590

.010^&

25(OH)D levels (N%)

12.200

.002^*

<50^a

13,778 (66.7)

1918 (69.8)

50–74.9^a

6220 (30.1)

761 (27.7)

≥75^a

650 (3.1)

67(2.4)

Maternal Age(years)

(Mean ± SD)

30.5 ± 3.7

30.2 ± 3.5

−2.759

.006^&

Maternal Age(years) (N(%))

17.364

.001^*

<24^a

628 (2.8)

14 (2.1)

25-29^a

9775 (42.4)

212 (44.9)

30–34

9351 (40.7)

244 (41.2)

≥35^a

3165 (14.1)

114 (11.7)

Pre-pregnancy BMI (kg/m2)

(Mean ± SD)

20.8 ± 3.6

21.1 ± 3.4

20.731

<.001^#

Pre-pregnancy BMI (kg/m) (N(%))

< 18.5^a

2813 (13.6)

326 (11.9)

18.5–23.9

15,105 (73.2)

1978 (72.0)

≥24^a

2730(13.2)

442 (16.1)

Season of blood collection

8.109

.044^*

Spring ^a

5132(24.9)

746 (27.2)

Summer

4910 (23.8)

642 (23.4)

Autumn

5314 (25.7)

660 (24.0)

Winter

5292(25.6)

698 (25.4)

No. of previous pregnancies

4.758

.093^*

0^a

13,311 (64.5)

1824 (66.4)

1

5072 (24.6)

650 (23.7)

2+

2265 (11.0)

272 (9.9)

Gestational age at birth, weeks

(Mean ± SD)

39.0 ± 1.2

38.2 ± 2.4

−10.445

<.001^&

Gestational age at birth (N(%))

1976.277

<.001^*

< 28

2

1

28–31 + 6

32 (.2)

48 (1.7)

32–33 + 6

13 (.1)

123 (4.5)

34–36 + 6

614 (3.0)

434 (15.8)

≥37

19,987 (96.8)

2140 (83.5)

Male (N%)

10,600 (51.3)

1463 (53.3)

3.655

.056^*

Cesarean section (N%)

8975 (43.5)

1069 (38.9)

22.366

<.001^*

2-h postpartum hemorrhage(ml)

241 ± 155

255 ± 137

−7.964

<.001^&

Apgar score(Mean ± SD)

9.9 ± .6

9.7 ± .9

−18.128

<.001^&

Apgar score

(N%)

233.297

<.001^*

0–3

37(.2)

8(.3)

4-6^a

97(.5)

54(2.0)

7-8^a

289(1.4)

127(4.6)

9-10^a

20,225(98.0)

2557(93.1)

Neonatal birth weight(g)

3366 ± 409

3172 ± 619

−12.208

<.001^&

Neonatal birth height(cm)

49.9 ± 1.1

49.2 ± 2.4

−12.976

<.001^&