Table 1.
Participant characteristics in a pregnancy cohort in Dhaka, Bangladesh, by intervention group.
| Characteristica | Intervention group (prenatal;postpartum vitamin D dose, IU/week) |
|||||
|---|---|---|---|---|---|---|
| Placebo (0;0) |
B (4200;0) |
C (16,800;0) |
D (28,000;0) |
E (28,000;28,000) |
Pb | |
| Number of participantsc | 200 | 121 | 133 | 114 | 122 | |
| Gestational age at enrollment | 20 (19, 22) | 21 (19, 22) | 20 (19, 22) | 20 (19, 22) | 21 (19, 22) | 0.63 |
| Age (years) | 22 (20, 26) | 22 (20, 25) | 22 (20, 25) | 22 (20, 27) | 23 (20, 27) | 0.78 |
| Height (cm) | 151.2 (5.4) | 150.9 (5.3) | 150.8 (5.8) | 149.7 (5.9) | 152.0 (5.4) | 0.03 |
| BMI at enrollment (kg/m2)d | 24.0 (4.2) | 23.3 (3.9) | 23.7 (4.1) | 23.6 (3.4) | 23.8 (4.0) | 0.69 |
| Asset index, n (%) | 0.12 | |||||
| 1 (lowest) | 44 (22) | 30 (25) | 19 (14) | 22 (19) | 22 (18) | |
| 2 | 36 (18) | 26 (22) | 32 (24) | 16 (14) | 17 (14) | |
| 3 | 47 (24) | 18 (15) | 21 (16) | 24 (21) | 22 (18) | |
| 4 | 34 (17) | 20 (17) | 29 (22) | 31 (27) | 34 (28) | |
| 5 (highest) | 39 (20) | 26 (22) | 32 (24) | 20 (18) | 27 (22) | |
| Education, n (%) | 0.26 | |||||
| No education | 4 (2.0) | 6 (5.0) | 9 (6.8) | 4 (3.5) | 3 (2.5) | |
| Primary incomplete | 39 (20) | 26 (21) | 21 (16) | 21 (18) | 26 (21) | |
| Primary complete | 28 (14) | 20 (17) | 10 (7.5) | 18 (16) | 21 (17) | |
| Secondary incomplete | 86 (43) | 36 (30) | 60 (45) | 43 (38) | 45 (37) | |
| Secondary complete | 43 (22) | 33 (27) | 33 (25) | 28 (25) | 27 (22) | |
| Occupation, n (%) | 0.93 | |||||
| Unemployed | 189 (95) | 113 (93) | 125 (94) | 107 (94) | 117 (96) | |
| Employed | 11 (5.5) | 8 (6.6) | 8 (6) | 7 (6.1) | 5 (4.1) | |
| Serum 25OHD at enrollment (nmol/L)d | 26.2 (17.4, 35.2) | 25.2 (16.3, 32.8) | 25.0 (17.7, 35.8) | 23.9 (16.2, 34.2) | 24.7 (17.4, 33.4) | 0.54 |
| Secondary hyperparathyroidism, n (%)e | 25 (13) | 9 (7.5) | 12 (9.1) | 16 (14) | 15 (12) | 0.43 |
| Serum 25OHD at delivery (nmol/L) | 21.8 (14.2, 29.5) | 66.0 (54.7, 77.6) | 101.5 (82.6, 116.3) | 110.1 (92.9, 128.5) | 111.1 (94.3, 132.7) | <0.001 |
| Serum 25OHD at 6 months postpartum (nmol/L) | 27.6 (20.1, 39.2) | 29.0 (21.7, 37.4) | 44.8 (36.3, 51.4) | 50.9 (43.9, 58.2) | 101.1 (90.9, 117.6) | <0.001 |
| Gestational duration (weeks) | 39 (38, 40) | 39 (38, 40) | 39 (38, 40) | 39 (38, 40) | 39 (39, 40) | 0.04 |
| Exclusive breastfeeding duration (weeks)f | 13 (3.75, 21) | 12 (6, 19) | 13 (4, 22) | 13 (5.5, 23) | 14.5 (4.5, 22) | 0.86 |
Data presented as median (25th percentile, 75th percentile) or mean (standard deviation) unless otherwise stated. 25OHD, 25-hydroxyvitamin D.
P-value from Kruskal-Wallis or ANOVA test for continuous variables and Chi-square test for categorical variables, as appropriate.
Sample sizes differed for the following variables: asset index (n = 120 in group B; n = 113 in group D), 25OHD at enrollment (n = 198 in group A; n = 120 in group B; n = 132 in group C; n = 113 in group D; n = 121 in group E), secondary hyperparathyroidism (n = 198 in group A; n = 120 in group B; n = 132 in group C; n = 113 in group D; n = 121 in group E), 25OHD at delivery (n = 130 in group A; n = 118 in group B; n = 128 in group C; n = 120 in group E), 25OHD at 6 months postpartum (n = 114 in group A; n = 118 in group B; n = 128 in group C; n = 111 in group D; n = 119 in group E), and gestational duration (n = 195 in group A).
Enrollment weight and height for BMI and samples for measurement of 25OHD were collected in the second trimester (17–24 weeks of gestation).
Secondary hyperparathyroidism was defined 25OHD concentration below 30 nmol/L and iPTH concentration >6.82 pmol/L.
Duration of exclusive breastfeeding was derived as the number of continuous weeks from birth to 26 weeks; however, all infants were assumed to be exclusively breastfed (received breastmilk only) in the first week of life.