Comment: The quality of evidence is downgraded by study limitations (unclear allocation concealment and blinding of outcome assessment).
Clinical comment: In most studies the intervention was started late in gestation or the time was not stated.
A Cochrane review «Lifestyle interventions for the treatment of women with gestational diabetes»1 «Brown J, Alwan NA, West J et al. Lifestyle interve...»1 included 15 studies with a total of 4501 women and 3768 infants. The lifestyle interventions included a wide variety of components such as education, diet, exercise and self-monitoring of blood glucose. The control group included usual antenatal care or diet alone. There was no clear evidence of a difference between lifestyle intervention and control groups for the risk of hypertensive disorders of pregnancy (pre-eclampsia), caesarean section, development of type 2 diabetes, perineal trauma/tearing, or induction of labour «Lifestyle interventions versus control - Maternal outcomes...»1. More women in the lifestyle intervention group had met postpartum weight goals one year after birth than in the control group «Lifestyle interventions versus control - Maternal outcomes...»1. Lifestyle interventions were associated with a reduction in the risk of being born large-for-gestational age (LGA) «Lifestyle versus control - Neonatal and later outcomes...»2. There was a trend for lower birthweight, neonatal fat mass, and the incidence of macrosomia in the lifestyle intervention group «Lifestyle versus control - Neonatal and later outcomes...»2.
| Outcomes | Relative effect (95% CI) | Risk with usual care/control | Risk with lifestyle intervention (95% CI) | № of participants (studies) Quality of evidence |
|---|---|---|---|---|
| Hypertensive disorders of pregnancy (pre-eclampsia) | RR 0.70 (0.40 to 1.22) | 129 per 1000 | 90 per 1000 (51 to 157) | (4 2796) Low |
| Perineal trauma/tear | RR 1.04 (0.93 to 1.18) | 498 per 1000 | 518 per 1000 (463 to 588) | 1000 (1) Moderate |
| Caesarean section | RR 0.90 (0.78 to 1.05) | 380 per 1000 | 342 per 1000 (296 to 399) | 3545 (10) Low |
| Induction of labour | RR 1.20 (0.99 to 1.46) | 211 per 1000 | 252 per 1000 (220 to 285) | 2699 (4) High |
| Postnatal depression | RR 0.49 (0.31 to 0.78) | 169 per 1000 | 83 per 1000 (53 to 132) | 573 (1) Low |
| Postnatal weight retention or return to pre-pregnancy weight | RR 1.75 (1.05 to 2.90) | 214 per 1000 | 375 per 1000 (225 to 621) | 156 (1) Low |
| Development of type 2 diabetes (follow-up) | RR 0.98 (0.54 to 1.76) | 83 per 1000 | 81 per 1000 (45 to 146) | 486 (2) Low |
| Outcomes | Relative effect (95% CI) | Risk with usual care/control | Risk with lifestyle intervention (95% CI) | № of participants (studies) Quality of evidence |
|---|---|---|---|---|
| Large-for-gestational age | RR 0.60 (0.50 to 0.71) | 189 per 1000 | 113 per 1000 (95 to 134) | 2994 (6) Moderate |
| Perinatal (fetal and neonatal death) and later infant mortality | RR 0.09 (0.01 to 1.70) | 5 per 1000 | 0 per 1000 (0 to 9) | 1988 (2) Low |
| Neonatal hypoglycaemia | RR 0.99 (0.65 to 1.52) | 75 per 1000 | 74 per 1000 (49 to 114) | 3000 (6) Moderate |
| Adiposity (neonatal) - Mean neonatal fat mass (g) | - | 427 g | 37.30 g fewer (63.97 fewer to 10.63 fewer) - | 958 (1) Low |
| Adiposity (child) - Childhood BMI > 85th percentile | RR 0.91 (0.75 to 1.11) | 350 per 1000 | 318 per 1000 (262 to 388) | 767 (3) Moderate |