Table 1 Distribution of blood manganese concentration and birth weight by general characteristics of the study subjects
From: Maternal blood manganese level and birth weight: a MOCEH birth cohort study
Maternal blood Mn (μg/L) | Birth weight (g) | |||||
|---|---|---|---|---|---|---|
N | (%) | Mean ± SD | p-value† | Mean ± SD | p-value† | |
Total | 331 | (100) | 22.5 ± 7.2 | - | 3,303.9 ± 367.6 | - |
Infant sex | ||||||
Male | 166 | (50.2) | 22.7 ± 7.5 | 0.521 | 3,359.2 ± 388.7 | 0.004 |
Female | 160 | (48.3) | 22.2 ± 6.5 | 3,242.6 ± 331.6 | ||
Missing | 5 | (1.5) | 25.4 ± 15.1 | - | 4060.0 | - |
Gestational age (days) | ||||||
<268 | 79 | (23.9) | 20.9 ± 8.1 | 0.067 | 3,252.4 ± 363.6 | <.001 |
268-272 | 73 | (22.0) | 22.9 ± 6.7 | 3,169.5 ± 333.6 | ||
273-277 | 54 | (16.3) | 22.8 ± 7.1 | 3,292.2 ± 346.0 | ||
278-282 | 67 | (20.2) | 23.1 ± 6.7 | 3,447.4 ± 385.8 | ||
≥283 | 58 | (17.5) | 23.2 ± 7.0 | 3,389.8 ± 346.2 | ||
Maternal age (years) | ||||||
<28 | 104 | (31.4) | 22.5 ± 7.6 | 0.781 | 3,312.6 ± 343.7 | 0.996 |
28-29 | 90 | (27.2) | 21.1 ± 6.8 | 3,282.2 ± 395.9 | ||
30-32 | 82 | (24.8) | 22.8 ± 6.7 | 3,326.3 ± 372.3 | ||
≥33 | 54 | (16.3) | 22.6 ± 7.8 | 3,296.4 ± 364.0 | ||
Missing | 1 | (0.3) | 29.8 | - | 2,920.0 | - |
Maternal education | ||||||
High school or less | 85 | (25.7) | 22.7 ± 7.3 | 0.794 | 3,337.5 ± 398.7 | 0.400 |
University or above | 230 | (69.5) | 22.5 ± 7.1 | 3,301.1 ± 359.7 | ||
Missing | 16 | (4.8) | 21.8 ± 8.2 | - | 3,166.9 ± 284.6 | - |
Maternal income (million KRW‡ per month) | ||||||
<200 | 81 | (24.5) | 22.8 ± 6.4 | 0.961 | 3,280.6 ± 391.4 | 0.276 |
200-299 | 117 | (35.3) | 21.8 ± 7.3 | 3,295.7 ± 375.6 | ||
≥300 | 118 | (35.6) | 22.9 ± 7.2 | 3,336.5 ± 349.7 | ||
Missing | 15 | (4.5) | 22.3 ± 9.7 | - | 3,233.6 ± 315.7 | - |
Maternal parity | ||||||
No | 134 | (40.5) | 22.3 ± 6.4 | 0.363 | 3,281.9 ± 358.9 | 0.821 |
≥1 | 151 | (45.6) | 22.4 ± 7.9 | 3,334.4 ± 370.5 | ||
Missing | 46 | (13.9) | 23.5 ± 6.9 | 3,265.0 ± 382.0 | ||
Maternal term weight (kg) | ||||||
<61 | 54 | (16.3) | 24.4 ± 8.5 | 0.736 | 3,182.4 ± 333.6 | 0.003 |
61-64 | 56 | (16.9) | 21.6 ± 7.0 | 3,244.6 ± 283.0 | ||
65-68 | 36 | (10.9) | 21.6 ± 6.5 | 3,251.4 ± 383.9 | ||
69-75 | 50 | (15.1) | 21.5 ± 4.5 | 3,368.4 ± 358.0 | ||
≥76 | 43 | (13.0) | 21.7 ± 7.8 | 3,519.3 ± 426.7 | ||
Missing | 92 | (27.8) | 23.2 ± 7.4 | 3,295.6 ± 361.2 | ||
Maternal blood Mn (μg/L)* | ||||||
<16.9 | 65 | (19.6) | - | - | 3,362.2 ± 386.6 | 0.167 |
16.9 – <20.0 | 66 | (19.9) | - | - | 3,225.3 ± 378.5 | |
20.0 – <22.9 | 68 | (20.5) | - | - | 3,355.5 ± 345.3 | |
22.9 – <26.9 | 66 | (19.9) | - | - | 3,270.2 ± 347.9 | |
>26.9 | 66 | (19.9) | - | - | 3,308.6 ± 371.5 | |
Birth weight (quintile, g) | ||||||
<3000 | 59 | (18.2) | 22.7 ± 8.6 | 0.608 | - | - |
3000-3199 | 65 | (20.0) | 21.5 ± 6.1 | - | - | |
3200-3399 | 66 | (20.3) | 21.8 ± 6.0 | - | - | |
3400-3599 | 64 | (19.7) | 22.8 ± 7.1 | - | - | |
≥3600 | 71 | (21.9) | 23.2 ± 7.4 | - | - | |