Table 4.
Included studies assessing maternal zinc status and GDM.
| Author, Country | Sample Size | Zinc Measure | Outcome of the Study |
|---|---|---|---|
| (1) Sample Type | |||
| (2) Time at Which Gestation Diet Was Assessed or Sample Collected | |||
| (3) Method of Analysis | |||
| [97] Bo, Italy a,b | 126 GDM and 84 aOGTT 294 uncomplicated |
Dietary zinc intake 24–28 weeks Food frequency questionnaire |
↓ mean (SD) daily zinc intake between GDM and aOGTT women and women with uncomplicated pregnancies. GDM: 8.5 (2.4) and aOGTT: 8.7 (2.5) vs. uncomplicated: 9.4 (2.8) mg/day, p = 0.007 |
| [98] Behboudi-Gandevani S, Iran a | 72 with GDM 961 uncomplicated |
Dietary zinc intake 14–20 weeks Semi-quantitative food frequency questionnaire |
NS in mean (SD) daily zinc intake between GDM and those with uncomplicated pregnancies. GDM: 6.91 (3.42) vs. uncomplicated: 10.1 (7.45) mg/day |
| Inadequate dietary zinc intake estimated to affect <17% of the studied population | |||
| [48] Borella, Italy a | 18 GDM 35 uncomplicated |
Heparin plasma zinc Collected in the third trimester Flame AAS |
↑ mean (SD) plasma zinc in GDM women compared to women with uncomplicated pregnancies. GDM: 766.6 (117.6) vs. uncomplicated: 627.5 (150) µg/L, p ˂0.001 |
| [35] Wang, China a,c | 46 GDM and 98 IGT 90 uncomplicated |
Plasma zinc Collection time not specified Inductively coupled plasma atomic emission spectroscopy |
NS in mean (SD) plasma zinc between women with IGT and women with uncomplicated pregnancies. IGT: 1080 (270) vs. uncomplicated: 1130 (330) μg/L NS mean (SD) plasma zinc between women with GDM and those with uncomplicated pregnancies. GDM:1020 (190) vs. uncomplicated: 1130 (330) μg/L |
| [38] Hyvonen-Dabek, Finland d | 5 GDM 10 uncomplicated |
Serum zinc Collection time not specified Particle induced X-ray emission |
NS mean (SD) serum zinc in women with GDM compared to women with uncomplicated pregnancies. GDM: 1070 (190) vs. uncomplicated: 1150 (220) µg/L |
| [99] Wibell, Sweden d | 20 GDM 13 uncomplicated |
Serum zinc Collected across gestation AAS |
NS mean (SD) serum zinc between women with GDM and those with uncomplicated pregnancies. GDM: 700 (100) vs. uncomplicated: 700 (80) μg/L |
| Inadequate dietary zinc intake estimated to affect ≥17% of the studied population | |||
| [98] Behboudi-Gandevani, Iran a | 72 with GDM 961 uncomplicated |
Serum zinc Collected 14–20 weeks Flame AAS |
NS mean serum zinc between GDM and women with uncomplicated pregnancies. GDM: 844 (440) vs. uncomplicated: 835 (444) μg/L |
| [100] Al-Saleh, Kuwait a | 30 GDM 30 uncomplicated |
Serum zinc Collected at delivery Furnace AAS |
NS mean (SEM) serum zinc in women with GDM compared to women with uncomplicated pregnancies. GDM: 610.3 (60.1) vs. uncomplicated: 656.2 (241.4) µg/L |
a GDM defined as high blood glucose levels in pregnant women who have not previously been diagnosed with diabetes which over a 3 h oral glucose tolerance test provided at least two values over the criteria of Carpenter and Coustan; b aOGTT defined as high blood glucose levels in pregnant women who have not previously been diagnosed with diabetes which over a 3 h oral glucose tolerance test provided one abnormal value over the criteria of Carpenter and Coustan; c IGT defined as women with blood glucose consistently higher than 7.8 mmol/L; d GDM diagnosed with an intravenous glucose tolerance test at 30 weeks gestation. Bold print signifies results that were significantly different. Abbreviations AAS: atomic absorption spectrometry; aOGTT: abnormal oral glucose tolerance test; BMI: body mass index; GDM: gestational diabetes mellitus; IGT: impaired glucose tolerance; OGTT: oral glucose tolerance test; SD: standard deviation.