Active and passive maternal smoking during pregnancy and birth outcomes: the Kyushu Okinawa Maternal and Child Health Study

Table 4 Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for birth outcomes and adjusted means of birth weight according to maternal environmental tobacco smoke (ETS) exposure at the time of the first questionnaire in 1427 mother-child pairs for mothers who never smoked during pregnancy

Passive maternal smoking status	Low birth weight		Preterm birth		Small-for-gestational-age		Adjusted mean of birth weight, g (95% CI)^a
Passive maternal smoking status	Rate (%)	OR (95% CI)^a	Rate (%)	OR (95% CI)^b	Rate (%)	OR (95% CI)^a	Adjusted mean of birth weight, g (95% CI)^a
ETS exposure at home
No (n = 911)	7.4	1.00	3.5	1.00	8.1	1.00	3014.3 (2993.0 − 3035.6)
Yes (n = 516)	7.4	0.88 (0.53 − 1.42)	3.5	0.91 (0.48 − 1.65)	6.6	0.80 (0.51 − 1.24)	3011.2 (2982.6 − 3039.7)
P ^c							0.86
ETS exposure at work
No (n = 1255)	7.5	1.00	3.5	1.00	7.7	1.00	3010.4 (2992.4 − 3028.4)
Yes (n = 172)	6.4	0.97 (0.44 − 1.94)	3.5	0.97 (0.36 − 2.23)	7.0	0.96 (0.48 − 1.78)	3033.2 (2983.1 − 3083.2)
P ^c							0.41

^a Adjustment for maternal age; region of residence; number of children; family structure; maternal education; maternal employment; alcohol consumption during the preceding month; body mass index; gestational age; and baby’s gender.
^b Adjustment for maternal age; region of residence; number of children; family structure; maternal education; maternal employment; alcohol consumption during the preceding month; body mass index; and baby’s gender.
^c P value was calculated by analysis of covariance.

ISSN: 1471-2393