Table 1.
Description of the study population and residential green space levels (500 m) by maternal characteristics, 2008-2018.
| Characteristics | Total births, N = 415,020 (%) |
Postpartum depression, N = 43,399 (%) |
Total street green space | Tree | Low-lying vegetation | Grass | NDVI | Land-cover green space | Tree canopy cover | Distance to the nearest park |
|---|---|---|---|---|---|---|---|---|---|---|
| Physical activity, minutes/week, mean (SD) | 79.5 (80.8) | 74.9 (76.3) | - | - | - | - | - | - | - | - |
| Maternal age, years | ||||||||||
| <25 | 80,513 (19.4) | 6758 (15.7) | 24.5 (3.5) | 14.7 (3.7) | 4.4 (1.4) | 5.4 (1.5) | 0.26 (0.06) | 11.8 (17.5) | 1.5 (1.8) | 0.56 (0.49) |
| 25–34 | 245,934 (59.3) | 25,936 (59.8) | 25.2 (4.0) | 15.3 (4.1) | 4.5 (1.4) | 5.3 (1.4) | 0.26 (0.06) | 12.4 (17.6) | 2.0 (2.2) | 0.52 (0.45) |
| ≥35 | 88,573 (21.3) | 10,705 (24.5) | 25.7 (4.3) | 15.9 (4.4) | 4.6 (1.4) | 5.2 (1.4) | 0.27 (0.06) | 12.1 (17.1) | 2.4 (2.6) | 0.49 (0.42) |
| Maternal race/ethnicity | ||||||||||
| African American | 31,896 (7.7) | 3602 (8.3) | 24.4 (3.3) | 14.3 (3.7) | 4.4 (1.3) | 5.6 (1.4) | 0.25 (0.05) | 9.8 (15.7) | 1.3 (1.7) | 0.53 (0.43) |
| Non-Hispanic Asian | 52,946 (12.8) | 2639 (6.1) | 25.7 (4.2) | 15.9 (4.4) | 4.7 (1.3) | 5.1 (1.2) | 0.27 (0.06) | 11.5 (16.1) | 2.6 (2.5) | 0.45 (0.36) |
| Hispanic | 213,543 (51.5) | 21,525 (49.6) | 24.6 (3.6) | 15.0 (3.8) | 4.3 (1.3) | 5.3 (1.4) | 0.26 (0.06) | 10.4 (16.0) | 1.6 (1.8) | 0.54 (0.45) |
| Non-Hispanic white | 105,728 (25.5) | 14,308 (33.0) | 26.2 (4.4) | 15.9 (4.7) | 4.9 (1.6) | 5.3 (1.6) | 0.28 (0.06) | 17.0 (20.3) | 2.6 (2.8) | 0.53 (0.50) |
| Multiple/other | 10,865 (2.6) | 1324 (3.0) | 25.3 (4.1) | 15.2 (4.3) | 4.8 (1.5) | 5.3 (1.5) | 0.27 (0.06) | 14.0 (18.2) | 2.1 (2.4) | 0.51 (0.44) |
| Maternal education | ||||||||||
| <College | 137,387 (33.1) | 13,258 (30.6) | 24.5 (3.6) | 14.7 (3.7) | 4.4 (1.4) | 5.3 (1.4) | 0.26 (0.06) | 11.7 (17.3) | 1.5 (1.8) | 0.55 (0.47) |
| College (<4 years) | 93,590 (22.6) | 11,342 (26.1) | 24.9 (3.7) | 15.1 (3.9) | 4.4 (1.4) | 5.4 (1.5) | 0.26 (0.06) | 11.4 (17.2) | 1.7 (2.0) | 0.55 (0.48) |
| College (≥4 years) | 184,043 (44.3) | 11,799 (43.3) | 25.8 (4.3) | 15.9 (4.4) | 4.7 (1.4) | 5.2 (1.4) | 0.27 (0.06) | 13.1 (17.7) | 2.5 (2.6) | 0.49 (0.42) |
| Block group median household income in 2013 | ||||||||||
| ≤$43,696 | 103,493 (25.0) | 9640 (22.3) | 24.0 (3.2) | 14.7 (3.3) | 4.2 (1.2) | 5.0 (1.4) | 0.24 (0.05) | 7.7 (14.5) | 1.2 (1.4) | 0.53 (0.44) |
| $43,697–$55,962 | 103,411 (25.0) | 10,846 (25.0) | 24.9 (3.6) | 15.3 (3.9) | 4.3 (1.3) | 5.4 (1.4) | 0.26 (0.05) | 10.5 (16.4) | 1.7 (1.8) | 0.57 (0.47) |
| $55,963–$71,602 | 103,473 (25.0) | 11,365 (26.3) | 25.4 (3.8) | 15.4 (4.2) | 4.6 (1.5) | 5.4 (1.4) | 0.27 (0.06) | 12.6 (17.1) | 2.1 (2.1) | 0.52 (0.45) |
| >$71,602 | 103,431 (25.0) | 11,427 (26.4) | 26.4 (4.7) | 16.0 (4.8) | 5.1 (1.5) | 5.3 (1.4) | 0.29 (0.06) | 18.2 (19.8) | 3.1 (3.0) | 0.46 (0.44) |
| Smoking | ||||||||||
| Never Smoker | 346,811 (83.6) | 32,546 (75.0) | 25.1 (4.0) | 15.3 (4.1) | 4.5 (1.4) | 5.3 (1.4) | 0.26 (0.06) | 12.1 (17.4) | 2.0 (2.3) | 0.52 (0.45) |
| Ever Smoker | 47,260 (11.4) | 7305 (16.8) | 25.4 (4.1) | 15.5 (4.2) | 4.6 (1.4) | 5.3 (1.5) | 0.26 (0.06) | 12.8 (17.8) | 2.1 (2.4) | 0.52 (0.44) |
| Smoking during pregnancy | 20,915 (5.0) | 3547 (8.2) | 25.1 (3.0) | 15.1 (4.0) | 4.5 (1.5) | 5.4 (1.5) | 0.26 (0.06) | 12.7 (18.3) | 1.8 (2.2) | 0.55 (0.51) |
| Passive smoker | ||||||||||
| Yes | 8789 (2.1) | 1080 (2.5) | 24.7 (3.7) | 14.8 (3.9) | 4.4 (1.5) | 5.5 (1.5) | 0.26 (0.06) | 12.3 (17.8) | 1.6 (1.9) | 0.56 (0.49) |
| No | 404,119 (97.9) | 42,212 (97.5) | 25.2 (4.0) | 15.3 (4.1) | 4.5 (1.4) | 5.3 (1.4) | 0.26 (0.06) | 12.2 (17.5) | 2.0 (2.3) | 0.52 (0.45) |
| Insurance type | ||||||||||
| MediCal (or Medicaid) | 40,142 (9.8) | 4996 (11.6) | 24.5 (3.4) | 14.7 (3.6) | 4.4 (1.4) | 5.4 (1.5) | 0.25 (0.06) | 11.7 (17.5) | 1.4 (1.7) | 0.56 (0.48) |
| Other | 367,918 (90.2) | 37,971 (88.4) | 25.2 (4.0) | 15.4 (4.2) | 4.6 (1.4) | 5.3 (1.4) | 0.26 (0.06) | 12.3 (17.4) | 2.1 (2.3) | 0.52 (0.45) |
| Season of conception | ||||||||||
| Warm (May–October) | 204,728 (49.3) | 20,976 (48.3) | 25.1 (4.0) | 15.3 (4.1) | 4.5 (1.4) | 5.3 (1.4) | 0.26 (0.06) | 12.3 (17.5) | 2.0 (2.3) | 0.52 (0.45) |
| Cool (November–April) | 210,292 (50.7) | 22,423 (51.7) | 25.2 (4.0) | 15.3 (4.1) | 4.5 (1.4) | 5.3 (1.4) | 0.26 (0.06) | 12.2 (17.4) | 2.0 (2.2) | 0.52 (0.45) |
NDVI, Normalized Difference Vegetation Index; Medical is Medicaid for Californians. Green space measures: mean (standard deviation, SD). The units are % for total street green space, tree, low-lying vegetation, grass, land-cover green space and tree canopy cover, and km for distance to the nearest park.