Table 1 Demographics and prenatal participant characteristics

 2009

64 (35.2%)

640 (35.2%)

NA

 2010

49 (26.9%)

490 (26.9%)

 2011–2012

69 (37.9%)

690 (37.9%)

 Normal

90 (49.5%)

900 (49.5%)

NA

 Emergency CS

92 (50.5%)

920 (50.5%)

Age, years

32.0 ± 5.1

31.9 ± 5.4

0.865

 One or more

77 (42.3%)

688 (37.8%)

0.233^a

 Prostaglandin

22 (12.1%)

156 (8.6%)

0.112^a

 Oxytocin

41 (22.5%)

479 (26.3%)

0.266^a

PIH

13 (7.1%)

116 (6.4%)

0.687^a

Preterm labor

68 (37.4%)

230 (12.6%)

< 0.001^a

Gestational week

37.8 ± 2.3

38.8 ± 1.7

< 0.001

SD for birth weight

-0.304 ± 1.032

0.003 ± 1.039

< 0.001

 Comprehensive

60 (33.0%)

992 (54.5%)

< 0.001^a

 Regional

122 (67.0%)

828 (45.5%)

 Weekday

122 (67.0%)

1344 (73.9%)

0.015^a

 Weekend

60 (33.0%)

476 (26.2%)

 Day

89 (48.9%)

1015 (55.4%)

0.088^a

 Quasi-night

44 (24.2%)

435 (23.9%)

 Night

49 (26.9%)

370 (20.3%)