Table 1.
Characteristics of the 35,370 participants in the Nurses' Health Study II and Nurses' Mothers Cohort according to maternal smoking during pregnancy, 1989–20071
| Maternal Smoking |
|||||
|---|---|---|---|---|---|
| No smoking during pregnancy |
Quit smoking during pregnancy |
Smoked throughout pregnancy |
|||
| 1–14 cigarettes/day |
15–24 cigarettes/day |
25+ cigarettes/day |
|||
| Total N | 26,125 | 1,400 | 4,924 | 2,496 | 425 |
| Age (years) | 45.9 (4.7) | 45.5 (4.6) | 45.7 (4.5) | 44.9 (4.4) | 44.4 (4.1) |
| Information from Mothers' Questionnaire | |||||
| Birthweight (g) | 3335 (503) | 3246 (507) | 3159 (512) | 3115 (509) | 3094 (536) |
| Gestational age (weeks) | 39.4 (2.3) | 39.5 (2.4) | 39.3 (2.4) | 39.2 (2.5) | 39.2 (2.4) |
| Mother's age at birth | 26.4 (5.1) | 25.4 (4.5) | 26.6 (4.7) | 25.8 (4.6) | 26.0 (4.9) |
| Father's age at birth | 29.2 (5.7) | 28.2 (5.4) | 29.1 (5.4) | 28.9 (5.4) | 29.2 (5.1) |
| Mother's prepregnancy BMI (kg/m2) | 21.4 (2.6) | 21.0 (2.4) | 20.9 (2.4) | 21.0 (2.6) | 21.3 (3.1) |
| Father's BMI (kg/m2) | 23.6 (2.8) | 23.5 (2.8) | 23.6 (2.8) | 23.6 (2.8) | 23.6 (2.8) |
| History of diabetes in mother (%) | 10.8 | 8.7 | 8.8 | 10.7 | 12.7 |
| History of diabetes in father (%) | 15.8 | 14.8 | 15.2 | 14.4 | 16.0 |
| Maternal weight gain during pregnancy (%) | |||||
| <14 lbs | 14.5 | 12.5 | 15.4 | 15.8 | 14.8 |
| 15–19 lbs | 21.1 | 16.2 | 21.3 | 19.5 | 23.6 |
| 20–29 lbs | 42.3 | 40.9 | 41.7 | 40.3 | 37.1 |
| 30–39 lbs | 17.0 | 22.4 | 16.4 | 18.2 | 16.8 |
| ≥40 lbs | 5.1 | 8.0 | 5.2 | 6.2 | 7.8 |
| Mother's education (%) | |||||
| <4 years of high school | 14.0 | 12.3 | 11.2 | 13.2 | 13.7 |
| 4 years of high school | 51.0 | 46.1 | 47.3 | 48.4 | 43.8 |
| 1–3 years of college | 24.7 | 29.1 | 30.0 | 27.4 | 27.5 |
| 4+ years of college | 10.3 | 12.5 | 11.6 | 11.0 | 14.9 |
| Father's education (%) | |||||
| <4 years of high school | 19.5 | 14.7 | 15.1 | 16.9 | 18.6 |
| 4 years of high school | 39.4 | 36.2 | 35.5 | 36.8 | 29.2 |
| 1–3 years of college | 19.3 | 24.0 | 22.7 | 21.7 | 20.7 |
| 4+ years of college | 21.8 | 25.1 | 26.7 | 24.5 | 31.6 |
| Parents owned home at time of birth (%) | 49.0 | 38.4 | 44.7 | 43.8 | 45.3 |
| Information from Nurses' Questionnaires | |||||
| BMI (kg/m2) in 2007 | 27.1 (6.1) | 27.2 (6.3) | 27.3 (6.2) | 27.8 (6.4) | 27.8 (6.3) |
| BMI (kg/m2) at age 18 | 21.0 (2.8) | 21.1 (2.8) | 21.2 (2.9) | 21.5 (3.0) | 21.6 (3.1) |
| Childhood body size2 | 2.7 (1.4) | 2.7 (1.3) | 2.8 (1.5) | 2.8 (1.5) | 2.9 (1.5) |
| Age at menarche (%) | |||||
| <11 years | 6.8 | 7.1 | 7.4 | 9.0 | 7.6 |
| 11 years | 15.9 | 17.4 | 16.9 | 17.7 | 19.1 |
| 12 years | 30.6 | 29.2 | 30.8 | 30.6 | 30.2 |
| 13 years | 28.3 | 28.5 | 26.5 | 26.4 | 27.8 |
| 14 years | 10.8 | 9.9 | 11.2 | 10.0 | 8.7 |
| ≥15 years | 7.6 | 7.9 | 7.2 | 6.4 | 6.6 |
| Nulliparous (%) | 18.4 | 17.7 | 18.7 | 18.4 | 19.3 |
| Number of children (among parous women) | 2.3 (0.9) | 2.3 (0.9) | 2.3 (0.9) | 2.3 (1.0) | 2.2 (0.9) |
| Age at first birth (among parous women) | 26.8 (4.7) | 26.9 (4.8) | 27.0 (4.9) | 27.0 (4.9) | 27.7 (5.2) |
| Physical activity (mets/wk)3 | 11.4 (28.5) | 12.6 (29.9) | 12.9 (30.2) | 12.5 (29.9) | 13.8 (30.9) |
| Caloric intake (kcal)3 | 1854 (508) | 1854 (495) | 1833 (492) | 1823 (490) | 1815 (487) |
| Alcohol intake (g/day)3 | 5.3 (9.0) | 6.4 (9.6) | 6.9 (10.6) | 6.4 (10.1) | 6.5 (10.0) |
| Ever smoker (%) | 30.1 | 38.4 | 39.3 | 37.7 | 37.4 |
| Husband's education (%) | |||||
| <High school | 0.6 | 0.7 | 0.4 | 0.6 | 0.5 |
| High school | 17.7 | 17.1 | 16.3 | 16.8 | 16.9 |
| 2 years of college | 19.0 | 16.7 | 19.0 | 18.6 | 24.5 |
| 4 years of college | 31.3 | 31.5 | 32.5 | 32.6 | 26.4 |
| Graduate school | 31.4 | 34.1 | 31.8 | 31.4 | 31.6 |
1
Data represent mean (standard deviation) unless otherwise indicated. Percentages may not add to 100% due to rounding.
2
Average of childhood body size at ages 5 and 10 years by 9-level figure drawing.
3
Caloric intake and alcohol intake measured in 2003 and physical activity measured in 2005.