Table 1.
Time trends in population characteristics
| 2001 (N=3005) |
2002 (N=4826) |
2003 (N=4390) |
2004 (N=4942) |
2005 (N=4833) |
2006 (N=6225) |
|
|---|---|---|---|---|---|---|
| Maternal age (yr) | ||||||
| % < 19 | 15.0 | 13.8 | 13.7 | 15.4 | 12.5 | 12.6 ** |
| % 19–24 | 57.3 | 56.0 | 56.0 | 54.4 | 53.7 | 50.8 *** |
| % 25–34 | 24.2 | 25.9 | 26.4 | 26.0 | 29.8 | 32.7 *** |
| % ≥ 35 | 3.5 | 4.3 | 3.8 | 4.1 | 4.0 | 3.9 * |
| Race | ||||||
| % White | 60.3 | 63.6 | 64.032.7 | 65.6 | 62.3 | 59.1 |
| % Black | 36.6 | 35.2 | 2.4 | 28.9 | 28.6 | 26.8 *** |
| % Hispanic | 2.2 | 2.4 | 0.9 | 4.6 | 8.3 | 13.0 *** |
| % Other | 0.91 | 0.7 | 0.9 | 0.7 | 1.2 *** | |
| % Primiparous | 40.3 | 39.2 | 40.4 | 41 | 36.3 | 39.9 |
| % Multiple births | 3.5 | 3.0 | 2.9 | 3.2 | 3.0 | 2.5* |
| Marital status | ||||||
| % Not married father identified | 26.7 | 29.5 | 29.9 | 32.1 | 33.0 | 34.1 *** |
| % Not married no father identified | 31.9 | 30.5 | 29.9 | 26.0 | 24.8 | 27.2 *** |
| % Married | 41.4 | 40.0 | 40.2 | 41.9 | 42.2 | 38.7 |
| Education | ||||||
| % < high school or low for age | 27.7 | 26.4 | 25.5 | 26.2 | 26.7 | 27.7 |
| % High School graduate | 54.5 | 54.6 | 54.1 | 53.5 | 52.1 | 50.4 *** |
| % Some college or college graduate | 17.8 | 19.0 | 20.3 | 20.3 | 21.2 | 21.9*** |
| Total number of risks recorded (mean) | 1.42 | 1.45 | 1.18 | 1.47 | 1.46 | 1.44** |
| Past Medical History % | ||||||
| Severe Asthma | 0.93 | 1.22 | 5.1 | 1.42 | 1.32 | 1.32 |
| Cardiac disease | 4.4 | 4.2 | 11.8 | 4.4 | 4.6 | 4.9 |
| Diabetes | 11.2 | 11.9 | 3.2 | 10.5 | 10.7 | 11.6 |
| Pulmonary disease | 2.9 | 2.9 | 4.1 | 3.1 | 3.1 | 3.2 |
| Renal disease | 2.4 | 3.6 | 4.6 | 3.3 | 4 | 3.9 ** |
| Systemic diseases | 4.1 | 4.3 | 0.11 | 5.4 | 5.5 | 5.8 *** |
| History of head injury | 0.07 | 0.12 | 1.73 | 0.08 | 0.06 | 0.19 |
| Epilepsy | 1.86 | 1.78 | 6.5 | 1.56 | 2.26 | 2.57 ** |
| Hypertension | 6.9 | 6.9 | 0.14 | 6.6 | 6.7 | 6.6 |
| HIV positive | 0.13 | 0.21 | 0.21 | 0.51 | 0.10 | 0.10 |
| Coagulation disorders | 0.17 | 0.23 | 5.1 | 0.24 | 0.10 | 0.32 |
| Past Obstetric History % | ||||||
| Prior fetal abnormality | 0.07 | 0.04 | 0.16 | 0.22 | 0.19 | 0.16 |
| Prior fetal / infant death | 7.8 | 6.5 | 5.7 | 5.7 | 5.1 | 5.5 *** |
| Prior preterm delivery | 4.2 | 3.5 | 3.5 | 3.9 | 3.3 | 2.7 |
| Pregnancy complications % with | ||||||
| Incompetent cervix | ||||||
| Hyperemesis > 14 weeks | 1.2 | 1.7 | 1.4 | 1.4 | 1.1 | 1.4 |
| Maternal anemia | 11.2 | 11.9 | 14.9 | 14.8 | 14.3 | 12.9 ** |
| Preeclampsia / eclampsia | 36.3 | 35.3 | 34.7 | 34.2 | 33.0 | 29.7 *** |
| PPROM | 4.9 | 5.1 | 4.9 | 4.7 | 5.6 | 5.7 * |
| Suspected fetal anomaly | 7.6 | 7.9 | 6.8 | 7.5 | 7.0 | 6.3 ** |
| Oligo/Polyhydramnios | 9.8 | 12.3 | 16.3 | 15.9 | 18.2 | 18.7 *** |
| Placenta previa | 0.17 | 0.25 | 0.46 | 0.49 | 0.64 | 0.37 * |
| 1.86 | 1.51 | 0.96 | 0.38 | 0.62 | 0.34 *** | |
| Gestational age at delivery (mean weeks) | 38.4 | 38.5 | 38.5 | 38.6 | 38.6 | 38.6 *** |
*
p < .05.
**
p < .01,
***
p < .001 C-A time trend test for frequencies, f test for means