Table 3.
Study characteristics of other cohort studies (Physical activity- PA based n = 5).
| Author, Year | Study name, duration | Participant size, country, mean (SD) BMI kg/m2, mean (SD) age years | Type of Exposure, time of exposure | Intervention assessment | GDM assessment | Results reported: Odds Ratio or Relative risk (95%CI, p value) or GDM incidence |
|---|---|---|---|---|---|---|
| Currie et al., 2014 [37] | -, October 2002 to July 2005 | n = 1,749, Canada, Mean age was 31 years, 49 % were nulliparous, and 41 % had a prepregnancy BMI of 25 kg/m2 or higher | Physical activity (High), a year before pregnancy | The Kaiser Physical Activity Survey, completed at approximately 20 weeks’ gestation, requested information regarding physical activity during the year before the pregnancy and the first 20 weeks of pregnancy. Outcomes were assessed by medical chart review | SOGC guidelines |
Associations were not observed between total physical activity and gestational diabetes |
| Dempsey et al., 2004 [38] | OMEGA Study, 1996–2000 | n = 909, USA |
Recreational physical activity (High), a year before pregnancy |
Women were questioned during early gestation about physical activity performed during the year before and 7 days prior to the interview during pregnancy | National Diabetes Data Group criteria | RR: 0.24 (0.10, 0.64) |
| Oken et al., 2006 [39] | Project Viva, 1999 to 2002 | n = 1,805 USA, Mean (standard deviation [SD]) age was 32.1 (5.0) years, and prepregnancy BMI was 24.6 (5.2) kg/m2 |
Physical activity (High), a year before pregnancy |
Assessed duration and intensity of physical activity and time spent viewing television both before and during pregnancy | National Diabetes Data Group criteria | OR: 0.56 (0.33–0.95) |
| Zhang et al., 2006 [40] | Nurses’ Health Study II, Between 1990 and 1998 | n = 21,765, USA |
Amount and intensity of pre-gravid physical activity and sedentary behavior (High), Pre-pregnancy |
Physical activity and sedentary behaviors were assessed through mailed questionnaires | National Diabetes Data Group criteria | RR: 0.77 (0.69–0.94, 0.002) |
| Zhang et al, 2014 [27] | Nurses’ Health Study II, 1989–2001 | n = 14437, USA |
Combination of lifestyle factors (Smoking, diet and physical activity) (High), Pre-pregnancy |
Questionnaires are administered biennially to update lifestyle characteristics | National Diabetes Data Group criteria | RR: 0.59 (0.48–0.71) |
SD Standard Deviation, CI Confidence interval, OR Odds Ratio, RR Relative Risk, SOGC The Society of Obstetricians and Gynaecologists of Canada.