Table 3.
Adjusted associations of maternal blood and hair (log10) Mn concentrations during pregnancy with fetal growth (among term births)a and length of gestation, ISA study, Costa Rica, 2010-2011 (n = 380).
| Exposure | Birth weight (g) |
Body length (cm) |
Ponderal index (g/cm3) |
Head circumference (cm) |
Chest circumference (cm) |
Length of gestation (days) |
||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n | β (95% CI) | n | β (95% CI) | n | β (95% CI) | n | β (95% CI) | n | β (95% CI) | n | β (95% CI) | |
| Blood Mn (ng/L)b, c | ||||||||||||
| By trimesters | ||||||||||||
| Trimester 1 | 88 | 1.5 (−9.7,12.7) | 87 | 0.03 (−0.03,0.09) | 87 | 0.00 (−0.01,0.01) | 86 | 0.02 (−0.03,0.06) | 56 | 0.04 (−0.01,0.09) | 94 | −0.23 (−0.68,0.21) |
| Trimester 2 | 258 | 2.4 (−5.2,10.1) # | 255 | −0.02 (−0.06,0.03) # | 255 | 0.01 (0.00,0.01) * | 253 | −0.01 (−0.04,0.02) | 128 | −0.02 (−0.06,0.03) | 276 | −0.06 (−0.33,0.20) # |
| Trimester 3 | 194 | 9.0 (0.5,17.5) ** | 190 | 0.03 (−0.02,0.08) | 190 | 0.00 (0.00,0.01) | 187 | 0.02 (−0.01,0.05) | 79 | 0.01 (−0.04,0.07) | 203 | −0.02 (−0.24,0.21) |
| Mean during pregnancy | 351 | 3.1 (−3.6,9.8) | 347 | 0.00 (−0.04,0.04) | 347 | 0.00 (0.00,0.01) | 343 | −0.01 (−0.03,0.02) | 153 | −0.02 (−0.06,0.02) | 375 | −0.10 (−0.31,0.12) |
| Hair Mn (μg/g)d, e | ||||||||||||
| By trimesters | ||||||||||||
| Trimester 1 | 95 | 28.9 (−113.9,171.7) | 94 | −0.18 (−0.92,0.57) | 94 | 0.07 (−0.03,0.18) | 93 | 0.19 (−0.37,0.76) | 60 | 0.26 (−0.48,0.99) | 101 | 2.61 (−2.75,7.98) |
| Trimester 2 | 274 | 68.8 (−18.2,155.8) | 270 | 0.13 (−0.37,0.63) | 270 | 0.04 (−0.04,0.11) | 268 | −0.02 (−0.33,0.29) | 133 | 0.62 (0.16,1.08) ** | 290 | −0.04 (−2.82,2.73) |
| Trimester 3 | 202 | 32.5 (−75.6,140.5) | 198 | −0.01 (−0.66,0.65) | 198 | 0.04 (−0.05,0.13) | 196 | −0.12 (−0.51,0.28) | 82 | 0.55 (−0.16,1.26) | 215 | −0.72 (−3.88,2.43) |
| Mean during pregnancy | 331 | 58.9 (−28.9,146.8) | 326 | 0.01 (−0.48,0.50) | 326 | 0.05 (−0.02,0.12) | 323 | −0.03 (−0.34,0.29) | 154 | 0.66 (0.19,1.13) ** | 352 | 0.68 (−2.09,3.44) |
Abbreviations: CI, confidence interval.
Models for birth weight, body length, ponderal index, head circumference, and chest circumference include only term births.
Results are for one-unit increase in blood Mn concentrations.
Adjusted for maternal education, parity, smoking during pregnancy, pre-pregnancy body mass index, infant sex, gestational diabetes, caffeinated tea intake during pregnancy, and timing of prenatal care initiation. Models for birth weight, body length, ponderal index, head circumference, and chest circumference also adjusted for length of gestation and length of gestation squared.
Results are for 10-fold increase in hair Mn concentrations.
Adjusted for maternal education, parity, smoking during pregnancy, pre-pregnancy body mass index, infant sex, maternal country of birth, vaginal bleeding in the first trimester of gestation (m = 28, 7.4%), caffeinated tea intake during pregnancy, iron intake during pregnancy, and maternal age. Models for birth weight, body length, ponderal index, head circumference, and chest circumference also adjusted for length of gestation and length of gestation squared.
pLinear < 0.10
pLinear < 0.05
pGAM < 0.05