. Author manuscript; available in PMC: 2013 Jul 12.

Published in final edited form as: Obstet Gynecol. 2013 Apr;121(4):798–804. doi: 10.1097/AOG.0b013e3182860b8d

Table 3.

Demographic Factors Associated With Focal Myometrial Contraction Development

	Focal Myometrial Contraction Present (n=115)	Focal Myometrial Contraction Absent (n=220)	Risk Ratio (95% CI)	P
Gestational age (wk)	18.9 (18.0–21.3)	23.0 (18.4–27.2)	0.90 (0.87–0.94)	<.001
Body mass index (kg/m²)	25.0 (21.4–29.0)	23.5 (21.4–26.5)	1.0 (1.0–1.1)	.03
Parity	1.0 (0.0–1.0)	0.0 (0.0–1.0)	1.3 (1.1–1.4)	<.001

CI, confidence interval.

Data are median (interquartile range) unless otherwise specified.