| Table 1: Demographic and clinical characteristics of 33 women recruited for breath and blood testing while pregnant | |
| Characteristic | Measure |
| Mean age, yr (and standard error of the mean [SEM]) | 30.4 (0.7) |
| Mean gestational age, wk (and SEM) | 29.1 (3.3) |
| Ethnic background, % of sample | |
| Asian- or African-American | 33.3 |
| Jewish Mediterranean | 30.0 |
| Northern European or North American | 36.6 |
| Gravidity, no. of women recruited | |
| Gravida 1 | 9 |
| Gravida 2 | 8 |
| Gravida 3 | 14 |
| Gravida 4 | 1 |
| Gravida 5 | 1 |
| Result of test for lactose breath hydrogen concentration* | |
| Positive | 18 |
| Negative | 12 |
| *One woman did not undergo lactose breath hydrogen testing but did undergo testing for oral-cecal transit time, and two women did not produce hydrogen. | |