Table 1 Characteristics associated with live births occurring between 2011 and 2018 among participants in the PROTECT cohorta
From: Preterm birth and PM2.5 in Puerto Rico: evidence from the PROTECT birth cohort
Characteristic | All births (N = 1092) | Term births (n = 993) | Preterm births (n = 99) |
|---|---|---|---|
Individual-level characteristics | |||
Infant sex | |||
Female | 519 (47.6) | 479 (48.3) | 40 (40.4) |
Male | 572 (52.4) | 513 (51.7) | 59 (59.6) |
Length of gestation, mean (SD), weeks | 38.5 (1.8) | 38.9 (1.1) | 34.9 (3.2) |
Mother’s age, mean (SD), years | 26.9 (5.5) | 26.9 (5.5) | 27.0 (5.6) |
Mother’s race | |||
Hispanic white | 573 (52.5) | 527 (53.1) | 46 (46.5) |
Black or other race | 498 (45.6) | 446 (44.9) | 52 (52.5) |
Mother’s level of educationb | |||
Less than high school | 76 (7.1) | 64 (6.6) | 12 (12.2) |
High school or technical school | 515 (47.9) | 462 (47.3) | 53 (54.1) |
College | 484 (45.0) | 451 (46.2) | 33 (33.7) |
Family income in past year, US dollars | |||
< 10,000 | 270 (24.7) | 231 (23.3) | 37 (37.4) |
10,000 – 29,999 | 308 (28.2) | 280 (28.2) | 25 (25.3) |
30,000 – 49,999 | 227 (20.8) | 211 (21.2) | 15 (15.2) |
≥ 50,000 | 138 (12.6) | 125 (12.6) | 11 (11.1) |
Consumed alcoholic drink on one or more days per week in past year | 176 (16.1) | 165 (16.6) | 11 (11.1) |
Drinks consumed per drinking occasion, past year | |||
0 | 584 (59.8) | 522 (59.0) | 62 (66.7) |
1–2 | 228 (23.3) | 209 (23.6) | 19 (20.4) |
3 or more | 165 (16.9) | 153 (17.3) | 12 (12.9) |
Ever smoked | 172 (15.9) | 160 (16.3) | 12 (12.2) |
Current smoker | 15 (1.4) | 13 (1.3) | 2 (2.0) |
Partner smokes at home | 107 (9.8) | 90 (9.1) | 17 (17.2) |
Birth weight, mean (SD), grams | 3161.9 (523.8) | 3235.1 (442.5) | 2415.4 (683.2) |
Number of pregnancies, including this one | |||
1 | 454 (41.6) | 415 (41.8) | 39 (39.4) |
2 | 392 (35.9) | 362 (36.5) | 30 (30.3) |
3 or more | 232 (21.2) | 203 (20.4) | 29 (29.3) |
Number of other children, excluding this one | |||
0 | 414 (37.9) | 377 (38.0) | 37 (37.4) |
1 | 420 (38.5) | 382 (38.5) | 38 (38.4) |
2 or more | 123 (11.3) | 105 (10.6) | 18 (18.2) |
Has ever experienced adverse birth outcome (spontaneous abortion, preterm birth, or premature birth) | 259 (23.7) | 228 (23.0) | 31 (31.3) |
Marital status at first visit | |||
Single or divorced | 209 (19.1) | 191 (19.2) | 18 (18.2) |
Married | 615 (56.3) | 569 (57.3) | 46 (46.5) |
Cohabiting | 255 (23.4) | 221 (22.3) | 34 (34.3) |
Employed at time of first visit | 688 (63.0) | 635 (63.9) | 53 (53.5) |
Pre-pregnancy BMI, mean (SD) | 25.2 (5.4) | 25.1 (5.4) | 26.6 (5.9) |
Maternal pre-pregnancy BMI | |||
Underweight (< 18.5) | 69 (6.3) | 65 (6.5) | 4 (4.0) |
Normal (18.5–24.9) | 500 (45.8) | 464 (46.7) | 36 (36.4) |
Overweight (25–29.9) | 284 (26.0) | 256 (25.8) | 28 (28.3) |
Obese (> 30) | 179 (16.4) | 158 (15.9) | 21 (21.2) |
Delivered by Caesarian section | 522 (47.8) | 464 (46.7) | 58 (58.6) |
Exercised at least 30 min per day in past year | 211 (19.3) | 193 (19.4) | 18 (18.2) |
Has a regular motorized commute (car, bus, train) | 952 (87.2) | 874 (88.0) | 78 (78.8) |
Municipal-level characteristicsc | |||
Median household income in 2013 inflation-adjusted US dollars, mean (SD) | 16,285.3 (2539.5) | 16,331.8 (2563.0) | 15,819.5 (2249.8) |
Population density per sq. mile, mean (SD) | 884.0 (384.3) | 890.7 (386.8) | 817.4 (353.6) |
% adults (> 25 yr) with < high school education, %, mean (SD) | 35.4 (5.5) | 35.3 (5.6) | 36.4 (4.9) |
% occupied units with 1 or more severe housing problems, mean (SD)d | 26.6 (8.9) | 26.7 (9.0) | 25.9 (8.1) |
% population that is non-white non-Hispanic, mean (SD) | 11.7 (8.3) | 11.6 (8.3) | 12.6 (8.8) |
Unemployment rate 2004–2013, %, mean (SD) | 16.2 (2.3) | 16.1 (2.3) | 16.7 (2.4) |
Mean age-adjusted diabetes prevalence 2004–2013, %, mean (SD) | 14.1 (0.6) | 14.1 (0.6) | 14.3 (0.5) |