Table 3

Results of multiple linear regression models predicting the difference between cord and maternal blood lead in a cohort of Pittsburgh, PA pregnant women, 1992–95

	All samples (n = 159)			All samples analysed shortly after delivery (n = 131)
	β	95% CI		β	95% CI
Positive association indicates increased relative amount of lead transferred.
Sample analysed in second batch	0.20	−0.03 to 0.44
Blood pressure, centred, per 10 mm Hg	−0.06	−0.20 to 0.08	Blood pressure, centred, per 10 mm Hg	−0.06	−0.20 to 0.08
Mean Hb, per 1 g/100 ml	−0.12	−0.22 to −0.02	Mean Hb, per 1 g/100 ml	−0.12	−0.22 to −0.02
Alcohol, 2nd interview, yes/no	0.36	0.14 to 0.58	Alcohol, 2nd interview, yes/no	0.33	0.10 to 0.55
Sickle cell trait	−0.76	−1.21 to −0.32	Sickle cell trait	−0.74	−1.17 to −0.30
Previous miscarriage	−0.20	−0.39 to −0.01	Previous miscarriage	−0.23	−0.43 to −0.03
Delivery in winter	0.12	−0.05 to 0.29	Delivery in winter	0.10	−0.08 to −0.28
Mother >30 y	−0.22	−0.44 to 0.00	Mother >30 y	−0.08	−0.32 to 0.16
Weight gain >40 lb	0.01	−0.16 to 0.19	Weight gain >40 lb	0.02	−0.17 to 0.20
Blood pressure × mother’s age >30	0.36	0.09 to 0.62	Blood pressure × mother’s age >30	0.35	0.07 to 0.64
Blood pressure × weight gain	0.26	0.04 to 0.47	Blood pressure × weight gain	0.28	0.05 to 0.50