Table 6 Associations of the intensity of maternal cigarette smoking in the third trimester with birth congenital anomalies

Congenital diaphragmatic hernia

 n (/10000)

1325 (1.16)

52 (1.70)

54 (2.02)

24 (2.08)

 RR (95% CI)

1.00

1.27 (0.95–1.68)

1.39 (1.05–1.84)

1.37 (0.91–2.07)

 P value

0.1031

0.0228

0.1308

Gastroschisis

 n (/10000)

2350 (2.06)

175 (5.73)

132 (4.95)

51 (4.43)

 RR (95% CI)

1.00

1.59 (1.35–1.87)

1.32 (1.10–1.59)

1.20 (0.91–1.59)

 P value

<0.0001

0.0025

0.2043

Limb reduction defect

 n (/10000)

1474 (1.29)

70 (2.29)

73 (2.74)

34 (2.95)

 RR (95% CI)

1.00

1.38 (1.08–1.77)

1.55 (1.21–1.98)

1.61 (1.14–2.28)

 P value

0.0100

0.0004

0.0075

Cleft lip with or without cleft palate

 n (/10000)

5762 (5.04)

229 (7.50)

223 (8.36)

108 (9.38)

 RR (95% CI)

1.00

1.20 (1.05–1.38)

1.23 (1.07–1.41)

1.33 (1.10–1.63)

 P value

0.0075

0.0032

0.0033

Cleft palate alone

 n (/10000)

2630 (2.3)

121 (3.96)

150 (5.62)

59 (5.12)

 RR (95% CI)

1.00

1.32 (1.09–1.59)

1.70 (1.43–2.02)

1.52 (1.16–1.97)

 P value

0.0042

<0.0001

0.0020

Any outcome*

 n (/10000)

13022 (11.39)

624 (20.45)

597 (22.38)

264 (22.92)

 RR (95% CI)

1.00

1.33 (1.22–1.44)

1.35 (1.24–1.47)

1.35 (1.19–1.52)

 P value

< 0.0001

< 0.0001

< 0.0001