Table 2.
Summary of findings in the included studies.
| Study Number | Patients (Cases vs. Controls) |
Average Age (Cases vs. Controls) | Gestational Age or SGA (Cases vs. Controls) | Infant Weight (kg) (Cases vs. Controls) | Vitamin D Intake (IU) | Beginning of Supplementation |
|---|---|---|---|---|---|---|
| 1 [23] Naghshineh et al. | 138 (68 vs. 70) | 25.0 vs. 24.8 | 37.7% vs. 37.2% | 3.1 vs. 2.8 | 600/day | <16 weeks |
| 2 [24] Sablok et al. | 180 (120 vs. 60) | NR | 8.0% vs. 19.2% | 2.6 vs. 2.4 | one dose of 60,000 or one dose of 120,000 | one dose between 14–20 weeks |
| 3 [25] Mirzakhani et al. | 816 (408 vs. 408) | 27.5 vs. 27.2 | 38.7% vs. 38.8% | NR | 4400/day vs. 400/day | Weeks 10–18 |
| 4 [26] Sasan et al. | 142 (70 vs. 72) | 32.0 vs. 29.8 | NR | NR | 50,000/two weeks | 14 weeks |
| 5 [27] Dahma et al. | 198 (139 vs. 59) | NR | NR | 2.9 vs. 2.7 | 4000/day vs. 2000/day | First trimester |
NR—not reported; IU—international units; cases—received vitamin D, controls—did not receive vitamin D supplementation; SGA—small for gestational age (at delivery).