. Author manuscript; available in PMC: 2011 Sep 16.

Published in final edited form as: J Matern Fetal Neonatal Med. 2008 Dec;21(12):902–916. doi: 10.1080/14767050802320357

Table II.

Demographic and clinical characteristics of patients presenting with spontaneous preterm labor with intact membranes

	PTL without IAI Term delivery (n=153)	p	PTL without IAI Preterm delivery (n=108)	p^a	PTL with IAI Preterm delivery (n=84)	p^b
Maternal age (years)	22 (19-29.8)	NS	22 (19-30)	NS	23 (20-28)	NS
Smoking	18.4 (28/152)	NS	10.4 (11/106)	<0.01	30 (24/80)	0.04
GA at amniocentesis (weeks)	31.9 (29.4-33.3)	NS	31.9 (29.8-33.1)	<0.01	28.7 (25.1-33)	<0.01
GA at delivery (weeks)	38.7 (38-39.7)	<0.01	34.6 (33.3-35.6)	<0.01	29.8 (25.6-33.3)	<0.01
Birthweight (grams)	3,170 (2,900-3,515)	<0.01	2,330 (1,940-2,678)	<0.01	1,310 (735-2,118)	<0.01

Values expressed as percentage (number) or median (interquartile range)

p: comparison between PTL who delivered at term and PTL without IAI

p^a: comparison between PTL who delivered preterm without IAI and PTL with IAI

p^b: comparison between PTL who delivered at term and PTL with IAI

PTL: preterm labor; GA: gestational age; BMI: body mass index; IAI: intra-amniotic infection/inflammation NS: not significant