. Author manuscript; available in PMC: 2006 Jun 1.

Published in final edited form as: J Perinat Med. 2005;33(4):306–313. doi: 10.1515/JPM.2005.051

Table 2.

Clinical and obstetrical characteristics of normal pregnant women without labor and patients with preterm labor and intact membranes

	Normal pregnancy no labor n = 64	Preterm labor n = 102	P
Maternal age (y)	23 (17–34)	23 (13–39)	0.4
Nulliparity	23 (35.9)	41 (40.2)	0.6
Smoking^a	12 (19)	30 (29.7)	0.1
Gestational age at venipuncture (wks)	30.7 (20–36.8)	29.8 (20.1–33.7)	0.1
Gestational age at delivery (wks)	39.5 (37–42)	32.8 (21–41.4)	<0.001^*
Birthweight (g)^b	3325 (2610–4030)	1870 (400–3750)	<0.001^*

Values are expressed as median (range) or number (percent)

Statistically significant, P < 0.05

Normal pregnancy no labor (n=63); preterm labor (n=101)

Preterm labor (n=100)