Presentation Title
Maternal blood arsenic levels and associations with birth weight-for-gestational age
Abstract
Background: Among highly exposed populations, arsenic exposure in utero is associated with decreased birth weight, however, less is known about potential effects of arsenic exposure in urban communities without contaminated sources such as drinking water.
Objective: Investigate the association of blood arsenic levels with birth weight-for-gestational age categories within a prospective birth cohort study.
Design/Methods: We analyzed 730 mother-infant dyads within the Programming Research in Obesity, GRowth, Environment and Social Stressors (PROGRESS) cohort in Mexico City. Total arsenic was measured in maternal blood samples from the 2nd and 3rd trimesters, at delivery, as well as from infant umbilical cord blood samples. Multivariable, logistic regression models adjusting for maternal age, pre-pregnancy BMI, parity, infant sex, socioeconomic position, and prenatal environmental tobacco smoke exposure were used to calculate odds ratios of small-for-gestational age and large-for-gestational age compared to appropriate-for-gestational age (AGA) per unit increase of log-transformed arsenic.
Results: Median (IQR) blood arsenic levels for maternal second trimester were 0.74 (0.34) μg/L, maternal third trimester 0.74 (0.41) μg/L, maternal at delivery 0.85 (0.70) μg/L, and infant cord 0.79 (0.65) μg/L. Maternal delivery and infant cord blood samples were most strongly correlated (spearman r = 0.65, p < 0.0001). Maternal arsenic levels at delivery were associated with significantly higher odds of both SGA (adj. OR=1.44, 95% CI: 1.08-1.93) and LGA (adj. OR=2.03, 95 % CI: 1.12-3.67) compared to AGA. Results were similar for cord blood.
Conclusion: We found that in a Mexico City birth cohort, higher maternal blood arsenic levels at delivery were associated with higher odds of both SGA and LGA. Determining modifiable factors that could be mitigated, such as sources of arsenic exposure, may be important for optimizing fetal growth to improve long-term health of children.
Primary Faculty Mentor Name
Heather Burris
Faculty/Staff Collaborators
Chitra Amarasiriwardena, Alejandra Cantoral-Preciado, Birgit Claus Henn, Hsiao-Hsien Leon Hsu, Alison P. Sanders, Katherine Svensson, Marcela Tamayo-Ortiz, Martha M Téllez-Rojo, Robert O. Wright, Heather H. Burris
Status
Undergraduate
Student College
Rubenstein School of Environmental and Natural Resources
Program/Major
Environmental Sciences
Primary Research Category
Health Sciences
Secondary Research Category
Food & Environment Studies
Maternal blood arsenic levels and associations with birth weight-for-gestational age
Background: Among highly exposed populations, arsenic exposure in utero is associated with decreased birth weight, however, less is known about potential effects of arsenic exposure in urban communities without contaminated sources such as drinking water.
Objective: Investigate the association of blood arsenic levels with birth weight-for-gestational age categories within a prospective birth cohort study.
Design/Methods: We analyzed 730 mother-infant dyads within the Programming Research in Obesity, GRowth, Environment and Social Stressors (PROGRESS) cohort in Mexico City. Total arsenic was measured in maternal blood samples from the 2nd and 3rd trimesters, at delivery, as well as from infant umbilical cord blood samples. Multivariable, logistic regression models adjusting for maternal age, pre-pregnancy BMI, parity, infant sex, socioeconomic position, and prenatal environmental tobacco smoke exposure were used to calculate odds ratios of small-for-gestational age and large-for-gestational age compared to appropriate-for-gestational age (AGA) per unit increase of log-transformed arsenic.
Results: Median (IQR) blood arsenic levels for maternal second trimester were 0.74 (0.34) μg/L, maternal third trimester 0.74 (0.41) μg/L, maternal at delivery 0.85 (0.70) μg/L, and infant cord 0.79 (0.65) μg/L. Maternal delivery and infant cord blood samples were most strongly correlated (spearman r = 0.65, p < 0.0001). Maternal arsenic levels at delivery were associated with significantly higher odds of both SGA (adj. OR=1.44, 95% CI: 1.08-1.93) and LGA (adj. OR=2.03, 95 % CI: 1.12-3.67) compared to AGA. Results were similar for cord blood.
Conclusion: We found that in a Mexico City birth cohort, higher maternal blood arsenic levels at delivery were associated with higher odds of both SGA and LGA. Determining modifiable factors that could be mitigated, such as sources of arsenic exposure, may be important for optimizing fetal growth to improve long-term health of children.