Table 2 Associations of the timing of maternal cigarette smoking with birth congenital anomalies

Gastroschisis

n (/10000)

2116 (1.92)

604 (5.35)

2263 (2.00)

457 (5.40)

2332 (2.04)

388 (5.36)

2350 (2.06)

358 (5.21)

RR (95% CI)

1.00

1.54 (1.40–1.70)

1.00

1.44 (1.29–1.61)

1.00

1.41 (1.25–1.58)

1.00

1.42 (1.26–1.61)

P value

< 0.0001

< 0.0001

< 0.0001

< 0.0001

Limb reduction defect

n (/10000)

1384 (1.26)

272 (2.41)

1433 (1.27)

222 (2.62)

1468 (1.29)

187 (2.58)

1474 (1.29)

177 (2.58)

RR (95% CI)

1.00

1.52 (1.31–1.75)

1.00

1.58 (1.35–1.84)

1.00

1.49 (1.27–1.76)

1.00

1.49 (1.26–1.76)

P value

< 0.0001

< 0.0001

< 0.0001

< 0.0001

Cleft palate alone

n (/10000)

2479 (2.25)

489 (4.33)

2554 (2.26)

413 (4.88)

2624 (2.30)

342 (4.72)

2630 (2.30)

330 (4.80)

RR (95% CI)

1.00

1.45 (1.30–1.61)

1.00

1.60 (1.43–1.79)

1.00

1.48 (1.31–1.67)

1.00

1.50 (1.33–1.70)

P value

< 0.0001

< 0.0001

< 0.0001

< 0.0001

Cleft lip with or without cleft palate

n (/10000)

5462 (4.96)

884 (7.82)

5660 (5.01)

685 (8.09)

5747 (5.03)

597 (8.25)

5762 (5.04)

560 (8.15)

RR (95% CI)

1.00

1.28 (1.18–1.38)

1.00

1.26 (1.16–1.37)

1.00

1.26 (1.15–1.38)

1.00

1.24 (1.13–1.36)

P value

< 0.0001

< 0.0001

< 0.0001

< 0.0001

Congenital diaphragmatic hernia

n (/10000)

1263 (1.15)

205 (1.81)

1314 (1.16)

154 (1.82)

1327 (1.16)

140 (1.93)

1325 (1.16)

130 (1.89)

RR (95% CI)

1.00

1.35 (1.15–1.58)

1.00

1.28 (1.07–1.53)

1.00

1.35 (1.12–1.63)

1.00

1.33 (1.10–1.62)

P value

0.0002

0.0072

0.0016

0.0036

Hypospadias*

n (/10000)

6680 (11.86)

875 (15.15)

6910 (11.96)

646 (14.91)

7011 (12.00)

543 (14.64)

7021 (12.01)

517 (14.69)

RR (95% CI)

1.00

1.15 (1.07–1.24)

1.00

1.12 (1.03–1.22)

1.00

1.09 (1.00–1.20)

1.00

1.10 (1.00–1.21)

P value

0.0003

0.0089

0.0557

0.0460

Omphalocele

n (/10000)

1045 (0.95)

163 (1.44)

1086 (0.96)

122 (1.44)

1105 (0.97)

103 (1.42)

1089 (0.95)

97 (1.41)

RR (95% CI)

1.00

1.22 (1.02–1.45)

1.00

1.15 (0.94–1.41)

1.00

1.12 (0.91–1.39)

1.00

1.17 (0.94–1.46)

P value

0.0319

0.1670

0.2905

0.1708

Down syndrome

n (/10000)

6040 (5.49)

620 (5.49)

6170 (5.46)

490 (5.79)

6243 (5.47)

416 (5.75)

6232 (5.45)

398 (5.79)

RR (95% CI)

1.00

1.03 (0.95–1.13)

1.00

1.03 (0.93–1.14)

1.00

0.99 (0.89–1.10)

1.00

1.00 (0.90–1.12)

P value

0.4795

0.5453

0.8583

0.9346

Suspected chromosomal disorder

n (/10000)

4814 (4.37)

597 (5.28)

4940 (4.37)

469 (5.54)

4999 (4.38)

410 (5.66)

4964 (4.34)

380 (5.53)

RR (95% CI)

1.00

1.09 (0.99–1.19)

1.00

1.09 (0.98–1.20)

1.00

1.09 (0.98–1.21)

1.00

1.08 (0.97–1.21)

P value

0.0681

0.1040

0.1109

0.1595

Anencephaly

n (/10000)

978 (0.89)

143 (1.27)

1010 (0.89)

111 (1.31)

1022 (0.90)

99 (1.37)

990 (0.87)

99 (1.44)

RR (95% CI)

1.00

1.02 (0.85–1.24)

1.00

0.98 (0.79–1.21)

1.00

1.00 (0.80–1.25)

1.00

1.14 (0.91–1.42)

P value

0.8090

0.8363

0.9929

0.2429

Cyanotic congenital heart disease

n (/10000)

5904 (5.36)

719 (6.36)

6075 (5.38)

551 (6.51)

6172 (5.41)

453 (6.26)

6150 (5.38)

428 (6.23)

RR (95% CI)

1.00

0.97 (0.89–1.05)

1.00

0.94 (0.86–1.03)

1.00

0.88 (0.79–0.97)

1.00

0.88 (0.80–0.98)

P value

0.4612

0.2049

0.0111

0.0184

Meningomyelocele/Spina bifida

n (/10000)

1555 (1.41)

183 (1.62)

1589 (1.41)

150 (1.77)

1611 (1.41)

128 (1.77)

1596 (1.40)

120 (1.75)

RR (95% CI)

1.00

0.89 (0.76–1.05)

1.00

0.95 (0.80–1.14)

1.00

0.93 (0.77–1.13)

1.00

0.94 (0.78–1.15)

P value

0.1726

0.5794

0.4770

0.5681

Any outcome^⁑

n (/10000)

18837 (17.11)

3208 (28.39)

19562 (17.32)

2482 (29.33)

12981 (11.37)

1582 (21.85)

13022 (11.39)

1485 (21.61)

RR (95% CI)

1.00

1.30 (1.25–1.36)

1.00

1.30 (1.24–1.36)

1.00

1.35 (1.27–1.43)

1.00

1.34 (1.26–1.42)

P value

< 0.0001

< 0.0001

< 0.0001

< 0.0001