Table 3.
Maternal and offspring characteristics by rotating night shift work history before pregnancy for 4,044 mothers of a total of 4,813 children born between 1989 and 1995 enrolled in GUTS2
| History of rotating night shift work | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Characteristic | Never worked rotating night shifts (n = 1,424) | <3 y (n = 1,254) | 3‐5 y (n = 946) | ≥6 y (n = 420) | Ever worked rotating night shifts (n = 2,620) | |||||
| Mean (SD) | % a | Mean (SD) | % | Mean (SD) | % | Mean (SD) | % | Mean (SD) | % | |
| Maternal age at deliveryb | 33.1 (3.5) | 33.2 (3.6) | 33.4 (3.5) | 35.0 (3.2) | 33.6 (3.5) | |||||
| BMI before pregnancy | 22.7 (3.9) | 22.7 (3.8) | 23.0 (3.9) | 23.3 (4.2) | 22.9 (3.9) | |||||
| AHEIc | 42.6 (10.4) | 43.5 (9.9) | 43.7 (10.2) | 44.3 (10.2) | 43.7 (10.0) | |||||
| Physical activity, METs/wkd | 18.9 (21.4) | 23.2 (31.4) | 22.4 (28.7) | 22.6 (31.1) | 22.8 (30.4) | |||||
| Smoking history before pregnancyb | ||||||||||
| Never | 75.3 | 74.0 | 73.1 | 63.2 | 71.9 | |||||
| Past | 18.2 | 19.6 | 20.2 | 26.3 | 20.9 | |||||
| Current | 6.5 | 6.4 | 6.7 | 10.5 | 7.2 | |||||
| Husband holds graduate degree | 31.9 | 36.5 | 37.1 | 31.1 | 35.9 | |||||
| Mom's chronotype | ||||||||||
| Definite morning type | 31.9 | 36.0 | 34.4 | 37.4 | 35.6 | |||||
| Intermediate type | 56.9 | 55.0 | 55.6 | 52.1 | 54.8 | |||||
| Definite evening type | 11.2 | 9.0 | 10.0 | 10.5 | 9.6 | |||||
| Parity before first included pregnancy | ||||||||||
| Nulliparity | 20.3 | 21.8 | 22.0 | 20.5 | 21.6 | |||||
| One previous pregnancy | 32.4 | 29.0 | 30.0 | 30.7 | 29.7 | |||||
| Two previous pregnancies | 24.0 | 25.8 | 26.0 | 25.2 | 25.8 | |||||
| Three previous pregnancies | 23.3 | 23.4 | 22.0 | 23.6 | 22.9 | |||||
| Number of pregnancies (n) | 1,683 | 1,507 | 1,132 | 491 | 3,130 | |||||
| Gestational diabetes | 4.9 | 5.9 | 5.1 | 6.5 | 5.7 | |||||
| Preeclampsia | 2.3 | 2.4 | 3.3 | 2.7 | 2.8 | |||||
| Gestational hypertension | 4.1 | 3.7 | 5.0 | 5.3 | 4.4 | |||||
| Cesarean delivery | 21.6 | 21.6 | 23.7 | 27.1 | 23.2 | |||||
| Gestational age ≥ 42 weeks | 4.7 | 4.8 | 4.3 | 4.9 | 4.7 | |||||
| Maternal change in BMI from before to after current pregnancy | 1.0 (1.7) | 1.0 (1.6) | 1.1 (1.7) | 1.0 (1.8) | 1.1 (1.7) | |||||
| Offspring sex | ||||||||||
| Male | 46.0 | 45.0 | 48.2 | 49.3 | 46.8 | |||||
| Female | 54.0 | 55.0 | 51.8 | 50.7 | 53.2 | |||||
| Offspring age at GUTS2 baseline, 2004 | 11.8 (1.2) | 11.6 (1.2) | 11.6 (1.2) | 11.6 (1.3) | 11.6 (1.2) | |||||
| Offspring Tanner stagee | 2.8 (1.3) | 2.6 (1.3) | 2.6 (1.3) | 2.7 (1.3) | 2.6 (1.3) | |||||
| Offspring sedentary behavior, h/wke | 4.0 (2.8) | 3.9 (2.7) | 3.9 (2.5) | 4.1 (2.4) | 3.9 (2.6) | |||||
METs, metabolic equivalent hours.
a
Percentages are of nonmissing values.
b
Recorded on the most recent questionnaire prior to conception of first included offspring.
c
Recorded in 1991.
d
One MET is proportional to the amount of energy spent sitting quietly for 1 hour.
e
At GUTS2 baseline (2004).