Table 3.
Weighted mean differences (WMD) from primary meta-analyses of effects of vitamin D supplementation during pregnancy on maternal and neonatal/infant outcomes
| Outcomes | Trials | Intervention-control comparisons | Participants | WMD (intervention versus control) (95% CI) | I2 (%) |
|---|---|---|---|---|---|
| Maternal | |||||
| Serum 25(OH)D concentration at/near delivery (nmol/L) | 32 | 42 | 5706 | 32.91* (27.19 to 38.62) | 96* |
| Neonatal/infant | |||||
| Birth weight (g) | 30 | 37 | 5273 | 58.33* (18.88 to 97.78) | 43* |
| Birth length (cm) | 19 | 21 | 3899 | 0.19 (−0.08 to 0.47) | 62* |
| Head circumference at birth (cm) | 17 | 18 | 3791 | 0.13 (−0.05 to 0.30) | 63* |
| Cord serum 25(OH)D concentration (nmol/L) | 20 | 28 | 2988 | 27.73* (21.57 to 33.88) | 96* |
| Gestational age at birth (weeks) | 19 | 23 | 3214 | −0.01 (−0.19 to 0.16) | 54* |
| Neonatal bone mineral content (g) | 2 | 2 | 690 | 1.09 (−0.64 to 2.81) | 0 |
| Infant bone mineral content (g) | 1 | 2 | 52 | −43.00* (−67.25 to −18.75) | 0 |
| Neonatal bone mineral density (g/cm2) | 2 | 2 | 690 | 0.00 (−0.003 to 0.004) | 0 |
| Infant bone mineral density (g/cm2) | 1 | 2 | 52 | −0.04* (−0.06 to −0.03) | 0 |
| Length at age 1 year (cm) | 2 | 2 | 251 | 1.30* (0.54 to 2.06) | 40 |
| Weight at age 1 year (g) | 2 | 2 | 252 | 290.62 (−5.04 to 586.29) | 47 |
| Head circumference at age 1 year (cm) | 2 | 2 | 248 | 0.09 (−0.28 to 0.45) | 0 |
| Length for age z score at 1 year† | 2 | 3 | 186 | 0.31 (−0.04 to 0.66) | 0 |
| Weight for age z score at 1 year† | 2 | 3 | 187 | 0.13 (−0.19 to 0.45) | 0 |
| Head circumference for age z score at 1 year† | 2 | 3 | 183 | 0.12 (−0.18 to 0.42) | 0 |
*P<0.05.
†Derived with WHO child growth standards.