Placental Pathology Associated with Household Air Pollution in a Cohort of Pregnant Women from Dar es Salaam, Tanzania.
Smoke from the burning of biomass fuels has been linked with adverse pregnancy outcomes such as low birth weight, stillbirth, and prematurity.



To identify potential underlying mechanisms of adverse perinatal outcomes, we explored the association of placental pathology with household air pollution in pregnant women from urban/periurban Tanzania who cook predominantly with charcoal.



Between 2011 and 2013, we measured personal exposures to fine particulate matter (PM2.5) and carbon monoxide (CO) over 72 hr among a cohort of Tanzanian pregnant women. Placentas were collected after delivery for examination. Placental pathologies of inflammatory, hypoxic, ischemic/hypertensive, infectious and thrombotic etiologies were diagnosed, blinded to exposure levels. Using multiple logistic regression, we explored the association of PM2.5 and CO exposure with placental pathology.



One hundred sixteen women had personal air exposure measurements and placental histopathology available for analysis. PM2.5 and CO exposures were moderate [geometric means (GSD) were 40.5 μg/m3 (17.3) and 2.21 ppm (1.47) respectively]; 88.6% of PM2.5 measurements exceeded World Health Organization air quality guidelines. We observed an increase in the odds (per 1-unit increase in exposure on the ln-scale) of fetal thrombotic vasculopathy (FTV) both with increasing PM2.5 [adjusted odds ratio (aOR) = 5.5; 95% CI: 1.1, 26.8] and CO measurements (aOR = 2.5; 95% CI: 1.0, 6.4) in adjusted models only. FTV also was more common among pregnancies complicated by stillbirth or low birth weight.



Fetal thrombosis may contribute to the adverse outcomes associated with household air pollution from cook stoves during pregnancy. Larger studies are necessary for confirmation. Citation: Wylie BJ, Matechi E, Kishashu Y, Fawzi W, Premji Z, Coull BA, Hauser R, Ezzati M, Roberts D. 2017. Placental pathology associated with household air pollution in a cohort of pregnant women from Dar es Salaam, Tanzania. Environ Health Perspect 125:134-140; http://dx.doi.org/10.1289/EHP256.
Department of Obstetrics/Gynecology, Massachusetts General Hospital, Boston, Massachusetts, USA.
Blair J
BJ
Wylie
Emmanuel
E
Matechi
Yahya
Y
Kishashu
Wafaie
W
Fawzi
Zul
Z
Premji
Brent A
BA
Coull
Russ
R
Hauser
Majid
M
Ezzati
Drucilla J
DJ
Roberts
D000328:Adult; D000393:Air Pollutants / Q000032:analysis; D000397:Air Pollution / Q000706:statistics & numerical data*; D016902:Air Pollution, Indoor / Q000706:statistics & numerical data*; D002248:Carbon Monoxide / Q000032:analysis; D003296:Cooking; D005191:Family Characteristics; D005260:Female; D006801:Humans; D018811:Maternal Exposure / Q000706:statistics & numerical data*; D052638:Particulate Matter / Q000032:analysis; D010920:Placenta / Q000473:pathology*; D011247:Pregnancy; D012906:Smoke / Q000032:analysis; D013636:Tanzania / Q000453:epidemiology
D000393:Air Pollutants; D052638:Particulate Matter; D012906:Smoke; D002248:Carbon Monoxide