Table 2.
Representation of GDM prevention trials (RCTs or meta-analysis of RCTs).
| Population | Interventions | Results | Additional information | Reference |
|---|---|---|---|---|
| 2,873 healthy pregnant women, low level of physical activity (exercising <20 min on <3 days per week), 1,434 intervention and 1,439 control group | Physical exercise programs that included low to moderate intensity exercises. No restrictions on frequency, duration, or type of training | Lower GDM risk (30% risk reduction) Lower maternal weight gain |
GDM risk reduction and lower weight gain especially with physical activity program performed throughout pregnancy. No serious adverse effects |
(119) |
| 4,983 women and their babies | Combined diet and exercise interventions compared with standard care | No GDM risk reduction. No difference in maternal weight gain |
Less preterm delivery; Comparable rates of cesarean section, LGA, stillbirth and neonatal death, shorter duration of hospital stay |
(120) |
| 132 women with BMI >25 kg/m2 | Four-step multidisciplinary antenatal care (continuity of obstetric provider, regular weighing, nutritional and psychological advice) vs standard obstetric antenatal care | Lower incidence of GDM (83% less). Lower maternal weight gain |
Comparable birth weight of newborns | (121) |
| 2,152 pregnant women, BMI ≥ 25 kg/m2, 10–20 weeks of pregnancy | Early lifestyle intervention consisting of healthy eating advice and increasing physical activity compared to routine measures | No GDM risk reduction.a No difference in maternal weight gaina |
LGA not significantly different, less infants in intervention group with weight >4 kg, no differences in hypertension, pre-eclampsia, cesarean section, NICU admission, and hypoglycemia | (122) |
| 1,555 pregnant women, BMI ≥ 30 kg/m2, 15–19 weeks of pregnancy | Behavioral intervention or standard antenatal care, once a week through eight health trainer-led sessions to endorse healthy eating | No GDM risk reduction.a Lower maternal weight gain.a |
LGA not significantly different, no significant differences in adverse birth outcomes. Increase in physical activity, reduction in dietary glycemic load, and maternal sum of skinfold thickness | (123) |
| 269 pregnant women, history of GDM or BMI ≥ 30 kg/m2, before 20 weeks gestation | Individualized combined lifestyle intervention, focus on diet, physical activity, and weight control | Lower GDM risk (39% risk reduction). Lower maternal weight gain |
Increase in physical activity and improvement of dietary quality | (124) |
| 150 pregnant women, BMI ≤ 29 kg/m2, before 20 weeks gestation | Randomization to three intervention groups: healthy eating (HE), physical activity (PA), and combined healthy eating and physical activity, following principles of motivational interviewing | No significant differences in GDM risk. Lower gestational weight gain in HE compared to PA |
Comparable HOMA indices in all three intervention groups. Fasting glucose lower in HE at 35–37 weeks compared to PA. 20% of all women under the weight gain target of <5 kg, in total after 37 weeks 32% GDM in obese pregnant women |
(125) |
| 436 pregnant women, BMI ≤ 29 kg/m2, before 20 weeks gestation | Four groups, healthy eating (HE), physical activity (PA), combined healthy eating and physical activity (HE + PA), usual care (UC), following principles of motivational interviewing | No significant differences in GDM risk. Lower gestational weight gain in HE + PA compared to UC |
No Improvements in glucose or insulin parameters or HOMA IR. Similar birth weight, LGA, or SGA rates |
(126) |
| 450 pregnant women, BMI ≥ 35 kg/m2, 12–18 weeks gestation | Metformin, at a dose of 3.0 g per day, or placebo | No significant differences in GDM risk.a Lower maternal weight gaina |
No significant difference in birth weight. Lower incidence of preeclampsia. Higher incidence of side effects in Metformin group |
(127) |
| 449 pregnant women, BMI ≥ 30 kg/m2, 12–16 weeks gestation | Metformin, at a dose of 2.5 g per day (maximum dose), or placebo | No significant differences in GDM risk.a No significant difference in maternal weight gaina |
No significant difference in birth weight. No significant differences in HOMA IR or other metabolic parameters.a No significant differences in combined adverse outcomes. Higher incidence of side effects in Metformin group |
(128) |
aSecondary outcomes.
RCT, randomized controlled trial; BMI, body mass index; GDM, gestational diabetes mellitus; HE, healthy eating; PA, physical activity; IR, insulin resistance; RR, relative risk; CI, confidence interval; NICU, neonatal intensive care unit; LGA, large for gestational age; SGA, small for gestational age.