| Observational studies | Randomized controlled trials | ||
---|---|---|---|---|
Outcomes | No. of studies | Risk ratio (95% CI)* | No. of studies | Risk ratio (95% CI) |
Fetal | ||||
 Intrauterine growth restriction | 2 | 1.06 (0.59 to 1.90) | 0 | NA |
 Placenta abruption | 2 | 1.06 (0.81 to 1.38) | 3 | 0.93 (0.01 to 101.99) |
 Spontaneous abortion | 1 | 0.46 (0.12 to 1.84) | 3 | 0.44 (0.03 to 6.83) |
 Pregnancy loss (still births and spontaneous abortions) | 4 | 0.81 (0.62 to 1.05) | 6 | 0.51 (0.25 to 1.05) |
Perinatal | ||||
 Postpartum hemorrhage | 2 | 1.16 (1.06 to 1.27) | 1 | 0.33 (0.06 to 1.89) |
 Premature rupture of membranes | 3 | 0.94 (0.52 to 1.70) | 0 | NA |
 Preterm delivery | 3 | 0.82 (0.13 to 4.98) | 4 | 0.72 (0.39 to 1.35) |
 Preterm labour | 2 | 1.05 (0.56 to 1.97) | 0 | NA |
 Still birth | 4 | 0.75 (0.39 to 1.42) | 0 | NA |
Neonatal | ||||
 APGAR under 7 at five minutes | 2 | 0.24 (0.00 to 68,937.70)* | 1 | 0.66 (0.11 to 3.95) |
 Low birth weight | 3 | 0.55 (0.03 to 11.63) | 2 | 0.86 (0.00 to 3722.22) |
 Neonatal death | 1 | 0.37 (0.02 to 6.83) | 1 | 0.33 (0.01 to 8.13) |