Table 1 Characteristics of the Buenos Aires, Argentina, preterm infant cohort

Neonate characteristics

 Sample size

14^a

93

 Birth weight (g)

925.9 ± 75.6

1187.9 ± 25.2

0.003

 Gestation age (weeks)

27.6 ± 0.7

30.3 ± 0.2

0.0000157

 Sex

Male 9

Male 31

0.0372

Female 5

Female 62

 Cumulative NICU O₂ (Days)

47.1 ± 5.2

7.8 ± 1.1

< 0.001

 Delivery room surfactant

1/12 (8%)

4/86 (5%)

0.302

Maternal characteristics

 Maternal race

0.0693

 European-Latin

11

68

 Criollos

0

14

 European-other

0

5

 Jewish

1

3

 Arab-Middle Eastern

1

0

 African Caribbean

0

1

 Native American

1

0

 Asian

0

1

 Unknown or refused

0

1

Maternal age (year)

32.2 ± 1.9

34.1 ± 0.5

0.211

Maternal smoking history^b

7/14 (50%)

25/93 (27%)

0.0795

Maternal antenatal steroid

13/13 (100%)

82/90 (91%)

0.333

Maternal preeclampsia

3/14 (21%)

25/93 (27%)

1

IUGR-reason for delivery

5/12 (42%)

33/90 (37%)

0.321

BMI

33.6 ± 1.8

34.1 ± 5.2

0.604

Education^c

9/4/0/1

63/20/5/5

0.849

Employed first trimester

10/13 (77%)

69/88 (78%)

0.886

Alcohol during pregnancy

0

1/88 (1%)

0.331

Chorioamnionitis

2/12 (17%)

6/85 (7%)

0.238

Asthma

0

0

1

Other respiratory disease

0

0

1

Fetal complications

 Fetal IUGR

5/12 (42%)

38/88 (43%)

0.460

 Fetal oligohydramnios

3/12 (25%)

11/88 (13%)

0.155