Vitamin D + calcium + other vitamins and minerals showed no clear difference in low birthweight (less than 2500 g) compared with calcium + other vitamins and minerals (but no vitamin D) (low certainty).
Vitamin D supplementation probably leads to lower low birthweight (less than 2500 g) compared with placebo or no intervention (moderate certainty).
It is very uncertain whether vitamin D + calcium supplementation changes low birthweight (less than 2500 g) compared with placebo or no intervention (very low certainty).
Summary of findings table ‐ Vitamin B12 supplementation showed no clear difference in low birthweight (< 2500 g) compared with placebo/no vitamin B12 supplementation (low certainty).
Any intermittent iron regimen (with or without other vitamins and… showed no clear difference in low birthweight (less than 2500 g) compared with daily regimen (with same vitamins and minerals)‐infant outcomes (low certainty).