Plain English summary
Background
Methods
Study design and data source
Quality of self-reported data
Maternal characteristics
Smoking status measures
Statistical analyses
Results
SMOKING STATUS % (95% CI) | |||||||||
---|---|---|---|---|---|---|---|---|---|
Three months before pregnancy at low intensity (n = 121,197) | Three months before pregnancy at high intensity (n = 244,473) | Smoking anytime during pregnancy (n = 279,063) | First trimester at low intensity(n = 112,072) | First trimester at high intensity (n = 160,506) | Second trimester at low intensity (n = 110,411) | Second trimester at high intensity (n = 122,130) | Third trimester at low intensity(n = 116,985) | Third trimester at high intensity (n = 103,731) | |
Overall % (95% CI) | 3.1 (3.1, 3.2) | 6.3 (6.3, 6.4) | 7.1 (7.0, 7.1) | 2.9 (2.8, 2.9) | 4.2 (4.1, 4.2) | 2.9 (2.8, 2.9) | 3.2 (3.1, 3.2) | 3.0 (3.0, 3.1) | 2.7 (2.6, 2.7) |
Maternal Characteristics | |||||||||
Race/ethnicity | |||||||||
Non-Hispanic White | 3.6 (3.5, 3.6) | 9.8 (9.8, 9.9) | 10.5 (10.4, 10.5) | 3.7 (3.6, 3.7) | 6.6 (6.5, 6.6) | 3.8 (3.7, 3.8) | 5.1 (5.0, 5.1) | 4.1 (4.1, 4.2) | 4.4 (4.3, 4.4) |
Non-Hispanic Black | 4.3 (4.2, 4.4) | 3.6 (3.5, 3.6) | 6.0 (5.9, 6.0) | 3.7 (3.6, 3.7) | 2.1 (2.1, 2.2) | 3.3 (3.2, 3.3) | 1.5 (1.4, 1.5) | 3.2 (3.1, 3.2) | 1.3 (1.2, 1.3) |
Hispanic | 1.6 (1.5, 1.6) | 1.3 (1.2, 1.3) | 1.8 (1.7, 1.8) | 1.0 (0.9, 1.0) | 0.7 (0.6, 0.7) | 0.8 (0.8, 0.9) | 0.5 (0.4, 0.5) | 0.8 (0.8, 0.9) | 0.4 (0.3, 0.4) |
Other race/ethnicity a | 2.7 (2.6, 2.7) | 3.4 (3.4, 3.5) | 4.5 (4.5, 4.6) | 2.3 (2.2, 2.3) | 2.2 (2.1, 2.2) | 2.1 (2.0, 2.1) | 1.5 (1.5, 1.6) | 2.1 (2.1, 2.2) | 1.2 (1.2, 1.3) |
Age (years) | |||||||||
< 20 | 4.4 (4.3, 4.5) | 7.1 (7.0, 7.3) | 8.5 (8.4, 8.6) | 4.0 (3.9, 4.1) | 4.2 (4.1, 4.3) | 3.7 (3.6, 3.8) | 2.9 (2.8, 2.9) | 3.8 (3.7, 3.9) | 2.3 (2.2, 2.4) |
20–24 | 4.9 (4.8, 4.9) | 9.3 (9.2, 9.4) | 10.7 (10.7, 10.8) | 4.6 (4.5, 4.6) | 5.9 (5.9, 6.0) | 4.4 (4.4, 4.5) | 4.3 (4.3, 4.4) | 4.7 (4.6, 4.7) | 3.6 (3.5, 3.6) |
25–29 | 3.4 (3.3, 3.4) | 7.1 (7.1, 7.2) | 8.2 (8.1, 8.2) | 3.2 (3.1, 3.2) | 4.8 (4.7, 4.8) | 3.2 (3.1, 3.2) | 3.7 (3.7, 3.8) | 3.4 (3.3, 3.4) | 3.2 (3.1, 3.2) |
30–34 | 2.2 (2.1, 2.2) | 4.7 (4.6, 4.7) | 5.2 (5.1, 5.2) | 2.0 (1.9, 2.0) | 3.1 (3.1, 3.2) | 2.0 (1.9, 2.0) | 2.5 (2.4. 2.5) | 2.1 (2.0, 2.1) | 2.1 (2.1, 2.2) |
35+ | 1.8 (1.7, 1.8) | 3.8 (3.7, 3.8) | 4.3 (4.2, 4.3) | 1.6 (1.5, 1.6) | 2.6 (2.5, 2.6) | 1.6 (1.5, 1.6) | 2.1 (2.0, 2.1) | 1.7 (1.6, 1.7) | 1.8 (1.7, 1.8) |
Education | |||||||||
Less than high school | 4.7 (4.6, 4.7) | 10.1 (10.0, 10.2) | 12.8 (12.8, 12.9) | 4.9 (4.9, 5.0) | 7.6 (7.6, 7.7) | 5.1 (5.1, 5.2) | 6.2 (6.1, 6.2) | 5.5 (5.4, 5.5) | 5.4 (5.3, 5.4) |
High School/GED b | 4.8 (4.7, 4.8) | 10.3 (10.3, 10.4) | 11.9 (11.9, 12.0) | 4.7 (4.7, 4.8) | 7.0 (6.9, 7.0) | 4.7 (4.7, 4.8) | 5.4 (5.3, 5.4) | 5.0 (5.0, 5.1) | 4.6 (4.5, 4.6) |
Some college/Assoc. | 3.6 (3.6, 3.7) | 7.1 (7.0, 7.1) | 7.6 (7.5, 7.6) | 3.2 (3.1, 3.2) | 4.2 (4.2, 4.3) | 3.0 (2.9, 3.0) | 3.0 (3.0, 3.1) | 3.2 (3.1, 3.2) | 2.5 (2.5, 2.6) |
Bachelor’s + | 0.8 (0.7, 0.8) | 0.9 (0.8, 0.9) | 0.8 (0.7, 0.8) | 0.4 (0.8, 0.9) | 0.4 (0.3, 0.4) | 0.3 (0.2, 0.3) | 0.2 (0.2, 0.2) | 0.3 (0.2, 0.3) | 0.2 (0.2, 0.2) |
SMOKING STATUS % (95% CI) | |||||||
---|---|---|---|---|---|---|---|
TOTAL (N = 275,101) | QUITTER-LOW (n = 35,161) | QUITTER-HIGH (n = 19,577) | MAINTAINER-LOW (n = 79,059) | MAINTAINER-HIGH (n = 101,540) | REDUCER (n = 37,926) | INCREASER (n = 1838) | |
Smoking in Early or Late pregnancy | Low intensity smoking in Early pregnancy only | High intensity smoking in Early pregnancy only | Low intensity smoking in Early and Low intensity smoking in Late pregnancy | High intensity smoking in Early and High intensity smoking in Late pregnancy | High intensity smoking in Early and Low intensity smoking in Late pregnancy | Low intensity smoking in Early and High intensity smoking in Late pregnancy | |
Overall % (95% CI) | 7.1 (7.0, 7.1) | 12.8 (12.5, 13.1) | 7.1 (6.7, 7.5) | 28.7 (28.4, 29.0) | 36.9 (36.6, 37.2) | 13.8 (13.5, 14.1) | 0.7 (0.3, 1.1) |
Maternal Characteristics | |||||||
Race/ethnicity | |||||||
Non-Hispanic White | 76.3 (76.2, 76.5) | 10.7 (10.6, 10.9) | 7.2 (7.1, 7.3) | 25.2 (25.0, 25.4) | 41.4 (41.2, 41.7) | 14.8 (14.6, 14.9) | 0.7 (0.6, 0.7) |
Non-Hispanic Black | 11.9 (11.8, 12.0) | 18.6 (18.2, 19.0) | 5.8 (5.5, 6.0) | 45.1 (44.5, 45.6) | 20.9 (20.4, 21.3) | 9.1 (8.8, 9.4) | 0.6 (0.5, 0.7) |
Hispanic | 5.8 (5.7, 5.9) | 23.3 (22.7, 24.0) | 8.4 (8.0, 8.8) | 36.4 (35.7, 37.2) | 20.6 (20.0, 21.3) | 10.6 (10.2, 11.1) | 0.6 (0.5, 0.7) |
Other race/ethnicity a | 6.0 (5.9, 6.1) | 17.3 (16.8, 17.9) | 7.2 (6.8, 7.6) | 34.5 (33.7, 35.2) | 26.8 (26.1, 27.5) | 13.5 (13.0, 14.0) | 0.7 (0.6, 0.9) |
Age (years) | |||||||
< 20 | 6.3 (6.2, 6.4) | 18.5 (18.0, 19.1) | 8.7 (8.3, 9.1) | 31.2 (30.5, 31.9) | 26.7 (26.0, 27.4) | 14.1 (13.6, 14.6) | 0.8 (0.7, 0.9) |
20–24 | 30.4 (30.2, 30.6) | 14.5 (14.2, 14.7) | 7.5 (7.3, 7.7) | 29.6 (29.3, 29.9) | 33.0 (32.7, 33.4) | 14.7 (14.5, 15.0) | 0.6 (0.6. 0.7) |
25–29 | 33.0 (32.8, 33.2) | 11.9 (11.7, 12.1) | 6.6 (6.5, 6.8) | 28.3 (28.0, 28.6) | 38.7 (38.4, 40.0) | 13.9 (13.6, 14.1) | 0.6 (0.6, 0.7) |
30–34 | 20.3 (20.2, 20.5) | 10.9 (10.6, 11.2) | 6.8 (6.6, 7.0) | 28.0 (27.6, 28.4) | 40.6 (40.2, 41.0) | 13.0 (12.7, 13.3) | 0.7 (0.6, 0.8) |
35+ | 10.0 (9.9, 10.1) | 10.7 (10.4, 11.1) | 7.2 (6.9, 7.5) | 27.4 (26.9, 28.0) | 41.8 (41.2, 42.3) | 12.2 (11.8, 12.6) | 0.8 (0.7, 0.9) |
Education | |||||||
Less than HS | 24.6 (24.5, 24.8) | 9.4 (9.2, 9.6) | 5.3 (5.1, 5.5) | 30.0 (29.6, 30.3) | 41.4 (40.1, 41.7) | 13.3 (13.0, 13.5) | 0.70 (0.7, 0.8) |
High School/GED b | 41.6 (41.4, 41.8) | 12.0 (11.8, 12.2) | 6.8 (6.7, 7.0) | 28.6 (28.3, 28.9) | 38.0 (37.7, 38.3) | 14.0 (13.8, 14.2) | 0.7 (0.6, 0.7) |
Some college | 30.4 (30.2, 30.5) | 15.4 (15.2, 15.7) | 8.6 (8.4, 8.8) | 27.9 (27.6, 28.2) | 33.1 (32.8, 33.4) | 14.4 (14.2, 14.7) | 0.6 (0.6, 0.7) |
Bachelor’s + | 3.5 (3.4, 3.5) | 23.5 (22.7, 24.4) | 11.2 (10.5, 11.8) | 29.3 (28.4, 30.2) | 25.3 (24.5, 26.2) | 10.0 (9.4, 10.6) | 0.7 (0.5, 0.9) |
Maternal Characteristic | Low-intensity smoking N = 35,161 (12.78%) | High-intensity smoking N = 19,577 (7.12%) | ||
---|---|---|---|---|
Maternal Race/ethnicity | aOR | 95% CI | aOR | 95% CI |
Non-Hispanic White (ref.) | 1 | 1 | 1 | 1 |
Non-Hispanic Black | 0.70 | 0.68, 0.72 | 0.32 | 0.30, 0.33 |
Hispanic | 0.24 | 0.23, 0.25 | 0.12 | 0.11, 0.13 |
Other race/ethnicity a | 0.79 | 0.76, 0.82 | 0.47 | 0.45, 0.50 |
Maternal Age (years) | ||||
< 20 | 1.22 | 1.17, 1.27 | 1.01 | 0.94, 1.06 |
20–24 | 1.26 | 1.23, 1.30 | 1.16 | 1.12, 1.21 |
25–29 (ref.) | 1 | 1 | 1 | 1 |
30–34 | 0.76 | 0.73, 0.78 | 0.88 | 0.85, 0.92 |
35+ | 0.66 | 0.63, 0.69 | 0.84 | 0.80, 0.89 |
Maternal Education | ||||
Less than high school | 1.05 | 1.01, 1.08 | 1.13 | 1.09, 1.18 |
High School/GED b (ref.) | 1 | 1 | 1 | 1 |
Some College | 0.79 | 0.77, 0.81 | 0.71 | 0.68, 0.73 |
Bachelor’s + | 0.12 | 0.12, 0.13 | 0.08 | 0.08, 0.09 |