Table 2.

 Baseline characteristics of participants. Values are means (SD) unless stated otherwise

Characteristic	Placebo (n=222)	L-arginine + vitamins (n=228)	Vitamins alone (n=222)	P value
Age (years)	28.2 (5.1)	28.0 (6.1)	27.6 (5.5)	0.47*
Gestational age at enrolment (weeks)	21.1 (4.7)	20.9 (4.6)	21.1 (5.3)	0.84*
Previous gestation with pre-eclampsia/first degree relative with pre-eclampsia	211/11	218/10	209/13	0.65†
Median (range) parity	2 (1-9)	2 (1-6)	2 (1-6)	0.09†
Median (range) vaginal deliveries	0 (0-5)	0 (0-3)	0 (0-6)	0.42†
Median (range) previous caesarean sections	1 (0-2)	1 (0-3)	1 (0-3)	0.48†
Median (range) abortions	0 (0-5)	0 (0-3)	0 (0-2)	0.13†
Systolic blood pressure at enrolment (mm Hg)	105.1 (9.8)	105.4 (8.8)	105.6 (8.8)	0.86*
Diastolic blood pressure at enrolment (mm Hg)	68.3 (9.1)	67.2 (8.7)	67.6 (7.9)	0.40*
Plasma L-arginine (µM)	21.9 (8.5)	22.7 (8.3)	21.9 (9.2)	0.52*
Pre-gestational body mass index	26.8 (4.9)	27.5 (5.3)	26.1 (4.1)	0.28*
Smoked during pregnancy	5	4	6	0.87†

*Analysis of variance.

†Kruskal-Wallis test.