Table 2.
25‐hydroxyvitamin D levels (nmol/L) by sample type and season. Median and interquartile ranges and proportions with sufficient (≥50), insufficient (<50), and deficient (<25) levels
| All | Jan–Mar | Apr–Jun | Jul–Sep | Oct–Dec | ||
|---|---|---|---|---|---|---|
|
Mother Pregnancy |
N | 608 | 143 | 183 | 157 | 125 |
| Median [IQR] | 76.5 (47.9–95.2) | 53.1 (36–79.2) | 76.9 (47.3–93.1) | 91.5 (72.4–120) | 73.5 (47.7–91) | |
| Sufficient n(%) | 444 (73%) | 77 (53.8%) | 130 (71%) | 146 (93%) | 91 (72.8%) | |
| (95%CI) | (69.4–76.4)% | (45.7–61.8)% | (64.1–77.1)% | (87.9–96)% | (64.4–79.8)% | |
| Insufficient n(%) | 164 (27%) | 66 (46.2%) | 53 (29%) | 11 (7%) | 34 (27.2%) | |
| (95%CI) | (23.6–30.6)% | (38.2–54.3)% | (22.9–35.9)% | (4–12.1)% | (20.2–35.6)% | |
| Deficient n(%) | 41 (6.7%) | 15 (10.5%) | 15 (8.2%) | 1 (.6%) | 10 (8%) | |
| (95%CI) | (5–9)% | (6.5–16.6)% | (5–13.1)% | (0–3.5)% | (4.4–14.1)% | |
|
Infant Cord blood |
N | 345 | 73 | 82 | 95 | 95 |
| Median [IQR] | 38.6 (24.6–56.1) | 30.5 (17.1–39.7) | 36.7 (23.6–51.7) | 53.6 (34.3–67.1) | 38.2 [24.5–52.7] | |
| Sufficient n(%) | 120 (34.8%) | 10 (13.7%) | 26 (31.7%) | 53 (55.8%) | 31 (32.6%) | |
| (95%CI) | (29.9–40)% | (7.6–23.4)% | (22.6–42.4)% | (45.8–65.4)% | (24–42.6)% | |
| Insufficient n(%) | 225 (65.2%) | 63 (86.3%) | 56 (68.3%) | 42 (44.2%) | 64 (67.4%) | |
| (95%CI) | (60–70.1)% | (76.6–92.4)% | (57.6–77.4)% | (34.6–54.2)% | (57.4–76)% | |
| Deficient n(%) | 89 (25.8%) | 27 (37%) | 23 (28%) | 14 (14.7%) | 25 (26.3%) | |
| (95%CI) | (21.5–30.7)% | (26.8–48.5)% | (19.5–38.6)% | (9–23.2)% | (18.5–36)% | |
|
Mother 4 months post birth |
N | 333 | 110 | 77 | 58 | 88 |
| Median [IQR] | 51.7 (35.9–72.5) | 41.1 (26.7–55.1) | 52.5 (39.6–70.5) | 75.1 (64.1–89.1) | 48.9 (36.2–68.5) | |
| Sufficient n(%) | 173 (52%) | 36 (32.7%) | 42 (54.5%) | 52 (89.7%) | 43 (48.9%) | |
| (95%CI) | (46.6–57.3)% | (24.7–41.9)% | (43.5–65.2)% | (79.2–95.2)% | (38.7–59.1)% | |
| Insufficient n(%) | 160 (48%) | 74 (67.3%) | 35 (45.5%) | 6 (10.3%) | 45 (51.1%) | |
| (95%CI) | (42.7–53.4)% | (58.1–75.3)% | (34.8–56.5)% | (4.8–20.8)% | (40.9–61.3)% | |
| Deficient n(%) | 36 (10.8%) | 24 (21.8%) | 5 (6.5%) | 0 (0%) | 7 (8%) | |
| (95%CI) | (7.9–14.6)% | (15.1–30.4)% | (2.8–14.3)% | (0–6.2)% | (3.9–15.5)% | |
|
Infant 4 months post birth |
N | 322 | 112 | 72 | 56 | 82 |
| Median [IQR] | 85.8 (54.3–104.5) | 82.2 (23.4–104) | 87.8 (66.8–103.1) | 88.1 (70.5–101.8) | 84.2 (53–109.5) | |
| Sufficient n(%) | 246 (76.4%) | 75 (67%) | 60 (83.3%) | 49 (87.5%) | 62 (75.6%) | |
| (95%CI) | (71.5–80.7)% | (57.8–75)% | (73.1–90.2)% | (76.4–93.8)% | (65.3–83.6)% | |
| Insufficient n(%) | 76 (23.6%) | 37 (33%) | 12 (16.7%) | 7 (12.5%) | 20 (24.4%) | |
| (95%CI) | (19.3–28.5)% | (25–42.2)% | (9.8–26.9)% | (6.2–23.6)% | (16.4–34.7)% | |
| Deficient n(%) | 43 (13.4%) | 30 (26.8%) | 3 (4.2%) | 2 (3.6%) | 8 (9.8%) | |
| (95%CI) | (10.1–17.5)% | (19.5–35.7)% | (1.4–11.5)% | (1–12.1)% | (5–18.1)% |