Skip to main content

Table 4 Preterm delivery results for daily bottled, cold tap, total tap, and total water intake

From: The relationship between water intake and foetal growth and preterm delivery in a prospective cohort study

 

Follow-up data

Average of baseline

and follow-up data

Exposure

n (%)

Unadjusted RR (95% CI)

Adjusted RR (95% CI)a

Adjusted RR (95% CI)a

Bottled water

    

   None

483 (25%)

1

1

1

   Any

1458 (75%)

1.2 (0.9, 1.8)

1.2 (0.8, 1.8)

0.8 (0.5, 1.4)

Cold tap water (ounces)b

   

   0-27

472 (24%)

1

1

1

   > 27-53

494 (25%)

0.8 (0.5, 1.2)

0.8 (0.5, 1.3)

0.9 (0.6, 1.4)

   > 53-91

485 (25%)

0.9 (0.6, 1.3)

0.9 (0.6, 1.4)

0.9 (0.6, 1.4)

   > 91

490 (25%)

0.8 (0.5, 1.1)

0.8 (0.5, 1.3)

1.0 (0.6, 1.5)

Per 20 ounce

1.0 (0.9, 1.0)

0.9 (0.7, 1.3)

0.9 (0.6, 1.3)

Total tap water (ounces)b

   

   0-30

493 (25%)

1

1

1

   > 30-61

483 (25%)

0.8 (0.5, 1.2)

0.8 (0.5, 1.2)

1.0 (0.6, 1.5)

   > 61-96

535 (28%)

0.7 (0.5, 1.1)

0.8 (0.5, 1.2)

1.2 (0.8, 1.9)

   > 96

429 (22%)

0.9 (0.6, 1.3)

1.0 (0.6, 1.5)

0.9 (0.6, 1.4)

Per 20 ounce

1.0 (0.9, 1.0)

0.9 (0.7, 1.2)

0.9 (0.6, 1.3)

Total water (ounces)b

   

   0-51

491 (25%)

1.0

1.0

1.0

   > 51-78

478 (25%)

1.0 (0.7, 1.6)

1.2 (0.7, 1.9)

1.1 (0.7, 1.7)

   > 78-114

481 (25%)

1.0 (0.7, 1.6)

1.1 (0.7, 1.8)

1.0 (0.6, 1.5)

   > 114

478 (25%)

1.2 (0.8, 1.8)

1.4 (0.9, 2.2)

1.2 (0.8, 1.9)

Per 20 ounce

1.0 (1.0, 1.1)

1.1 (0.9, 1.4)

1.1 (0.8, 1.5)

  1. aAdjusted for race, education level, annual household income, smoking, pre-pregnancy BMI, vitamin use, parity, employed during last 4 months, infant gender, and study site
  2. bCategorical exposure cutpoints for average data results were slightly higher than the follow-up data
  3. BMI= body mass index; RR= risk ratio