Table 4.
Study characteristics of other cohort studies (Diet based n = 16).
| Author, Year | Study name, duration | Participant size, country | Type of Exposure, time of Exposure | Intervention assessment | GDM assessment | Results reported: Odds Ratio or Relative risk (95%CI, p value) or GDM incidence |
|---|---|---|---|---|---|---|
| Bao et al., 2015 [42] | Nurses’ Health Study II (NHS II), 1989–2001 | n = 21,411, USA | Low carbohydrate diet scores (A higher score indicates higher intake of fat and protein and lower intake of carbohydrate), Pre-pregnancy | Prepregnancy LCD scores were calculated from validated food-frequency questionnaires | National Diabetes Data Group criteria | Overall LCD score RR: 1.27 (1.06–1.51, 0.03) |
| Chen et al., 2009 [45] | Nurses’ Health Study II, 1989–2001 | n = 13,475, USA | Low intake (0–3 servings/month) of sugar-sweetened beverage consumption vs high intake (1–4 servings/week and >5 servings/week), Pre-pregnancy | Dietary intake information was collected by a 133-item SFFQ designed to assess average food intake over the previous year. For beverages, one serving (considered as one glass, bottle, or can) was used as the unit for the consumption of ssbs | National Diabetes Data Group criteria | RR:1.22 (1.01–1.47, 0.04) |
| Looman et al., 2018 [47] | Australian Longitudinal Study on Women’s Health (ALSWH), 2003 and 2015 | n = 3607, Australia |
Dietary carbohydrate quantity and quality (Low carb & high fiber), Pre-pregnancy |
Diet was assessed using the Dietary Questionnaire for Epidemiological Studies (DQES) | Diagnostic criteria for GDM in Australia | Low carb & High fiber RR: 0·67 (0·45, 0·96) |
| Mikel et al., 2018 [50] | SUN cohort, December 1999 and March 2012 | n = 3396, Spain |
Low Soft drink consumption (Low risk - rarely or never or <1/month), Pre-pregnancy |
A validated 136-item semi-quantitative food frequency questionnaire was used to assess soft drink consumption | National Diabetes Data Group criteria | High consumption: OR 2.03 (1.25–3.31) |
| Lynn et al., 2020 [48] | He Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-To-Be (numom2b), 2010 to 2013 | n = 8259, USA | High Healthy Eating Index (HEI) – 2010 score, Pre-pregnancy (3 months around conception) | Women completed the modified Block 2005 Food Frequency Questionnaire, a semiquantitative assessment of usual dietary intake for the 3 months around conception | National Diabetes Data Group criteria | There were no differences in frequency of GDM or cesarean delivery by HEI quartile on bivariable analysis |
| Mikel et al., 2019 [51] | SUN cohort, December 1999 and March 2012 | n = 3455, Spain | High DDS Dietary-Based Diabetes- Risk Score, Pre-pregnancy | A validated 136-item semi-quantitative FFQ was used to assess pre-gestational dietary habits | National Diabetes Data Group criteria | OR: 0·48 (0·24, 0·99, 0·01) |
| Tobias et al., 2012 [53] | Nurses’ Health Study II, 1989–2001 | n = 21, 376, USA | High Alternative Healthy eating index scores (derived from USDA Food Guide Pyramid and the 1995 Dietary Guidelines for Americans), Pre-pregnancy | Prepregnancy dietary pattern adherence scores were computed based on participants’ usual intake of the patterns’ components, assessed with a validated food-frequency questionnaire | National Diabetes Data Group criteria | HEI RR: 0.54 (0.43–0.68, <0.0001) |
| Zhang et al., 2014 [27] | Nurses’ Health Study II, 1989–2001 | n = 13,110, USA | High Alternate Healthy Eating Index-2010 diet score, Pre-pregnancy | Every four years thereafter, participants were asked to complete a semiquantitative food frequency questionnaire in addition to the main questionnaire | National Diabetes Data Group criteria | Total fiber: RR 0.70 (0.52–0.96) |
| Amelia et al., 2017 [41] | SUN cohort, December 1999 and March 2012 | n = 3298, Spain | Low Meat consumption and iron intake (Median 33.7 g/day), Pre-pregnancy | Meat consumption and iron intake were assessed at baseline through a validated, 136-item semi-quantitative, food frequency questionnaire. | National Diabetes Data Group criteria | Total meat: OR 1.67 (1.06–2.63, 0.010) |
| Bao et al., 2014 [42] | Nurses’ Health Study II (NHS II), 1989–2001 | n = 15027, USA |
Fried food consumption (Low), Pre-pregnancy |
Collected diet information, including consumption of fried foods at home and away from home, using a validated food frequency questionnaire | National Diabetes Data Group criteria | For who consumed Fried food >7 times/week RR: 2.18 (1.53–3.09, <0.001) |
| Bao et al., 2018 [43] | Nurses’ Health Study II (NHS II), 1989–2001 | n = 15225, USA |
Habitual intake of vitamin D from diet and supplements (High vitamin), Pre-pregnancy |
Diet information, including vitamin D intake from food sources and supplements, was assessed by validated food frequency questionnaires | National Diabetes Data Group criteria |
RR 1–399 IU/day: 0.80 (0.67–0.96, 0.002) ≥400 IU/day: 0.71 (0.56–0.90, 0.002) |
| Li et al., 2019 [46] | Nurses’ Health Study II, 1989–2001 | n = 14,553, USA | Adequate Habitual Intakes Folate (from food and supplement) ( ≥400 μg/day), Pre-pregnancy | Prepregnancy intakes of total folate, supplemental folate, and food folate were assessed using a food frequency questionnaire administered every 4 years | National Diabetes Data Group criteria | OR: 0.83 (0.72, 0,95, 0.007) |
| Mikel et al., 2017 [49] | SUN cohort, December 1999 and March 2012 | n = 3455, Spain | Adherence to Mediterranean dietary pattern, Pre-pregnancy | The 136 food items included in the FFQ were classified in twenty-six predefined food groups. | National Diabetes Data Group criteria | OR: 0·24 (0·10, 0·55) |
| Schoenaker et al., 2015 [52] | Australian Longitudinal Study on Women’s Health (ALSWH), 2003 and 2015 | n = 3853, Australia | Low risk diet- low meats, snacks and sweets consumption, Pre-pregnancy | Pre-pregnancy dietary patterns were derived using factor analysis based on 101 food items from a validated food frequency questionnaire | Diagnostic criteria for GDM in Australia | OR: 0.85 (0.76, 0.98) |
| Zhang et al., 2006 [54] | Nurses’ Health Study II, 1989–2001 | n = 13,110, USA | Low risk prudent diet (positively correlated with intakes of fruits, green leafy vegetables, poultry and fish), Pre-pregnancy | Dietary intake information was collected using a 133-food item semi-quantitative FFQ designed to assess average food intake over the previous year | National Diabetes Data Group criteria |
Prudent pattern RR: 1.39 (1.08–1.80, 0.018) |
| Zhang et al., 2006 [55] | Nurses’ Health Study II, 1989–2001 | n = 14,437, USA | High fiber intake ( >22 g/day), Pre-pregnancy | Dietary intake information was collected by a 133-food SFFQ designed to assess average food intake over the previous year | National Diabetes Data Group criteria | RR: 0.81 (0.70–0.94) |
SD Standard Deviation, CI Confidence interval, OR Odds Ratio, RR Relative Risk.