Table 1 Meta-analysis of the effect of diet, physical activity, metformin or dietary supplement on gestational diabetes prevention.

From: Participant characteristics in the prevention of gestational diabetes as evidence for precision medicine: a systematic review and meta-analysis

Intervention type

Number of studies

Number of participants

Risk Ratio (95% CI)

I2 (%)

Certainty by GRADE

Downgrade explanations

Diet

17

7509

0.78 (0.65–0.94)

45.6

Moderate

Most studies have Some Concerns or High risk of bias

Physical activity

19

6701

0.70 (0.57–0.87)

28.6

Moderate

Most studies have Some Concerns or High risk of bias

Diet and physical activity

59

22,026

0.82 (0.73–0.91)

47

Low

Most studies have Some Concerns or a High risk of bias;

High levels of heterogeneity

Metformin

13

3120

0.66 (0.47–0.93)

73

Very low

Most studies have Some Concerns or High risk of bias;

High levels of heterogeneity;

Egger test suggests significant publication bias

Myoinositol

7

1313

0.39 (0.23–0.66)

79

Very low

Most studies have Some Concerns or High risk of bias;

Very high levels of heterogeneity

Probiotics

5

1105

0.87 (0.52–1.46)

73.2

Very low

Most studies have Some Concerns or High risk of bias;

Very high levels of heterogeneity;

Pooled CI crosses 1.0 suggesting imprecision