Table 2.
Maternal characteristics in women with and without oligohydramnios
| With Oligohydramnios | No Oligohydramnios | Overall | p-Value1 | |
|---|---|---|---|---|
| At least one US exam ≥28 weeks, n | 87 | 12,853 | 12,940 | |
| Maternal age (years), n (%) | 87 | 12,849 | 12,936 | 0.2766 |
| < 20 | 17 (19.5) | 2185 (17.0) | 2202 (17.0) | |
| 20–35 | 61 (70.1) | 9577 (74.5) | 9638 (74.5) | |
| > 35 | 9 (10.3) | 1087 (8.5) | 1096 (8.5) | |
| Maternal education, n (%) | 87 | 12,851 | 12,938 | 0.1698 |
| No formal schooling | 30 (34.5) | 3209 (25.0) | 3239 (25.0) | |
| Primary | 37 (42.5) | 4403 (34.3) | 4440 (34.3) | |
| Secondary | 19 (21.8) | 4873 (37.9) | 4892 (37.8) | |
| University | 1 (1.1) | 366 (2.8) | 367 (2.8) | |
| Parity, n (%) | 82 | 12,660 | 12,742 | 0.1253 |
| 0 | 25 (30.5) | 2993 (23.6) | 3018 (23.7) | |
| 1 | 14 (17.1) | 2847 (22.5) | 2861 (22.5) | |
| 2+ | 43 (52.4) | 6820 (53.9) | 6863 (53.9) | |
| Previous live birth among multipara, n/N (%) | 52/57 (91.2) | 9092/9667 (94.1) | 9144/9724 (94.0) | 0.5814 |
| Previous live birth with primipara in denominator, n/N (%) | 52/82 (63.4) | 9092/12,660 (71.8) | 9144/12,742 (71.8) | 0.0421 |
| Maternal height, Mean (sd) | 151.1 (7.6) | 153.5 (8.1) | 153.5 (8.1) | 0.7097 |
| Maternal weight, Mean (sd) | 55.1 (10.0) | 55.9 (10.1) | 55.9 (10.1) | 0.0713 |
| Maternal BMI, Mean (sd) | 24.2 (4.2) | 23.8 (4.2) | 23.8 (4.2) | 0.1007 |
1P-value from a logistic regression model for at least one oligohydramnios finding adjusting for site and maternal characteristics using general estimating equations to account for the correlation of outcomes within cluster