Table 1:

Characteristics of mothers, by study period

Variable	Mean (95% CI)		p value
Variable	Control vaccine	Influenza vaccine	p value
No influenza virus circulating (Sept. 2004–Jan. 2005)	n = 108	n = 103
Gestational age at vaccination, wk	31.9 (31.6–32.3)	31.9 (31.5–32.2)	0.8
Gestational age at delivery, wk	39.3 (38.9–39.6)	39.4 (39.1–39.8)	0.6
Interval between vaccination and birth, d	51.5 (48.2–54.8)	52.5 (49.3–55.8)	0.7
Age, yr	25.0 (24.4–25.8)	25.5 (24.6–26.3)	0.4
Parity	1.1 (1.0–1.3)	1.2 (1.1–1.4)	0.4
Height, cm	152.5 (151.2–153.8)	153.1 (151.9–154.1)	0.5
Weight,^* kg	56.2 (54.4–58.0)	56.5 (54.8–58.3)	0.8
Influenza virus circulating (Feb. 2005–Oct. 2005)	n = 58	n = 58
Gestational age at vaccination, wk	30.5 (30.1–31.0)	31.5 (31.0–32.0)	0.01
Gestational age at delivery, wk	39.7 (39.3–40.1)	39.7 (39.3–40.1)	0.9
Interval between vaccination and delivery, d	63.9 (59.8–68.0)	57.4 (53.8–61.1)	0.02
Age, yr	24.9 (23.7–26.1)	24.7 (23.7–25.7)	0.8
Parity	1.3 (1.0–1.5)	0.9 (0.7–1.1)	0.1
Height, cm	153.0 (151.6–154.5)	152.9 (151.6–154.2)	0.9
Weight,^* kg	54.0 (51.4–56.7)	53.9 (51.8–55.9)	0.9