Table 2 Crude and adjusted odds ratios for the associations between average shower length and risk for birth defects, National Birth Defects Prevention Study, USA, 2000-2007

Controls

 <15 minutes

3,229 (48.7)

-

-

-

-

 ≥15 minutes

3,405 (51.3)

-

-

-

-

Anencephaly

 <15 minutes

152 (41.3)

1.00

1.00

 ≥15 minutes

216 (58.7)

1.35

1.09-1.67

1.22

0.96-1.56

Spina bifida

 <15 minutes

311 (42.8)

1.00

1.00

 ≥15 minutes

416 (57.2)

1.27

1.09-1.48

1.23

1.03-1.46

Cleft lip with or without cleft palate

 <15 minutes

752 (42.5)

1.00

1.00

 ≥15 minutes

1,016 (57.5)

1.27

1.14-1.41

1.14

1.01-1.28

Cleft palate without cleft lip

 <15 minutes

441 (47.8)

1.00

1.00

 ≥15 minutes

481 (52.2)

1.03

0.89-1.18

1.08

0.93-1.26

Microphthalmia^b

 <15 minutes

64 (45.4)

1.00

1.00

 ≥15 minutes

77 (54.6)

1.14

0.82-1.60

0.97

0.70-1.40

Cataract

 <15 minutes

125 (50.4)

1.00

1.00

 ≥15 minutes

123 (49.6)

0.93

0.72-1.20

1.02

0.77-1.34

Esophageal atresia

 <15 minutes

199 (49.5)

1.00

1.00

 ≥15 minutes

203 (50.5)

0.97

0.79-1.18

1.00

0.80-1.24

Gastroschisis

 <15 minutes

235 (29.4)

1.00

1.00

 ≥15 minutes

564 (70.6)

2.28

1.94-2.67

1.43

1.18-1.72

Omphalocele

 <15 minutes

115 (44.1)

1.00

1.00

 ≥15 minutes

146 (55.9)

1.20

0.94-1.54

1.16

0.89-1.53

Renal agenesis^c

 <15 minutes

40 (39.2)

1.00

1.00

 ≥15 minutes

62 (60.8)

1.47

0.99-2.19

1.24

0.79-1.95

Diaphragmatic hernia

 <15 minutes

242 (47.1)

1.00

1.00

 ≥15 minutes

272 (52.9)

1.07

0.89-1.28

1.07

0.88-1.31

Limb reduction defects

 <15 minutes

306 (43.9)

1.00

1.00

 ≥15 minutes

391 (56.1)

1.21

1.04-1.42

1.17

0.98-1.39

Hypospadias

 <15 minutes

715 (52.6)

1.00

1.00

 ≥15 minutes

645 (47.4)

0.85

0.75-0.96

1.11

0.96-1.29