Intake of tapwater and total water by pregnant and lactating women

Background. Despite theoretically higher requirements for water due to physiologic demands of pregnancy and lactation, little is known of actual ranges of intake in pregnant and lactating women. Methods. Population-based estimates of total water and tapwater intake in women of reproductive age were derived using data from the 1977-78 USDA Nationwide Food Consumption Survey. Three-day average intakes were calculated for 188 pregnant women, 77 lactating women, and 6,201 non-pregnant, non-lactating control women. Results. Total water intake (mean ± SD) was 1,940 ± 686 g/day (median 1,835) for control women, 2,076 ± 743 g/day (median 1,928) for pregnant women and 2,242 ± 658 g/day (median 2,164) for lactating women. Tapwater intake was 1,157 ± 635 g/day (median 1,065) for control women, 1,189 ± 699 g/day (median 1,063) for pregnant women, and 1,310 ± 591 g/day (median 1,330) for lactating women. Total water intake was equal to or greater than 3,000 g/day among 7 percent of control women, 11 percent of pregnant women, and 13 percent of lactating women. Tapwater intake was equal to or greater than 2,000 g/day among 10 percent of control women, 15 percent of pregnant women, and 8 percent of lactating women. Conclusions. These results should be useful in estimating amounts of nutrients and toxic substances that women of reproductive age obtain through the water supply.