Humid heat exposures over pregnancy impact birth outcomes but mechanisms are poorly described. We leveraged the Ghana Randomized Air Pollution and Health Study (GRAPHS) to examine associations between maximum shaded wet bulb globe temperature (WBGT) and cord blood extracellular vesicle (EV)-associated microRNA. We also considered heat index (HI) and dry air temperature as secondary exposures. Cord blood was collected at delivery and EVs isolated and RNAs sequenced and small RNA libraries constructed. We assigned participants' trimester and whole pregnancy average heat exposures using satellite reanalysis heat exposures at the level of participant community of residence. We then performed linear regression to examine associations between prenatal heat exposures and log2-transformed miRNA counts and considered significance with an unadjusted P-value ≤ .01 and |beta| > 0.2. In 44 participants, we identified 91 microRNAs that were detected in at least 70% of samples. We identified that miR-146b-5p (β = 0.94 [95% CI = 0.27, 1.6], per 1-degree increase in WBGT); miR-381-3p (β = 2.23 [1.3, 3.15]), miR-378a-3p (β = -1.4, [-2.42, -0.39]), and miR-744-5p (β = 1.51 [0.46, 2.57]); and miR-126-3p (β = -0.75 [-1.2, -0.29]) were associated with first-, second-, and third-trimester WBGT, respectively. miR-1307-3p (β = 2.27 [0.61, 3.94] per 1-degree increase in WBGT) was associated with WBGT averaged over the whole pregnancy. Similar findings were observed with HI. In the GRAPHS cohort, we identified that humid-heat exposure over pregnancy alters the cord blood EV-associated miRNA profiles.

IntroductionThe Harmattan season (approximately December to March) in Western Africa is characterized by dry, dusty trade winds blowing from the Sahara Desert toward the Gulf of Guinea and is associated with marked increases in fine particulate matter and other air pollutants, cooler temperatures, and crop reductions. The season has been linked with several negative health effects, though impacts on pregnancy outcomes are unknown. We leveraged data from the Ghana Randomized Air Pollution and Health Study (GRAPHS) to determine whether prenatal exposure to the Harmattan season impacts newborn size and whether there are critical windows of exposure.MethodsGRAPHS enrolled 1,414 pregnant women from Kintampo, Ghana from 2013 to 2015. We employed distributed lag models (DLMs) to examine time-varying associations between prenatal exposure to the Harmattan season (yes/no) for each week of gestation and birth weight, length, and head circumference among infants liveborn ≥ 37 weeks.ResultsAnalyses included n = 1,261 mother-infant pairs. Harmattan exposure was associated with smaller head circumference across gestation and DLMs identified sensitive windows in weeks 1–11 and 15–34. These effects were only significant among infant males. No impact of Harmattan on birth weight or birth length was identified.DiscussionOur analyses suggest prenatal exposure to the Harmattan season is associated with negative impacts on newborn size and specifically head circumference; exposure during certain gestational windows appears to have a greater impact than others. Climate change threatens to make Harmattan more severe secondary to increased desertification; we therefore need a better understanding of its health effects during pregnancy.

BACKGROUND:There is limited evidence on the long-term effects of household air pollution (HAP) exposure during critical developmental windows and longitudinal growth trajectories in childhood. METHODS:We leveraged a longitudinal pregnancy cohort from rural communities in central Ghana with repeated personal monitoring of prenatal and postnatal carbon monoxide (CO) and fine particulates (PM2.5). Child growth was measured at 1 year of age (n = 919), and annually from age 4 through 9 years (n = 698). Using generalized linear mixed-effects models adjusted for relevant confounders, we quantified separately, the age-specific associations between prenatal and postnatal CO and PM2.5, and z-scores of height-for-age (HAZ), weight-for-age (WAZ) and body mass index (BMI)-for-age (BMIZ) in primary models. Secondary models assessed the risk of being in a worse growth category compared with a better category e.g., for HAZ, stunted or at risk of stunting versus normal, or stunted versus at risk or normal). RESULTS:Prenatal CO had the most consistent association with growth. Higher prenatal CO was associated with lower HAZ from age 1 through 9 with peak effect at age 4: adjusted β = -0.08; 95% CI = -0.12, -0.03; p = 0.002 per doubling), and WAZ from 7 through age 9 (peak effect was at age 9: adjusted β = -0.05; 95% CI = -0.09, -0.003; p = 0.04 per doubling). Results were similar for the ordered categories of HAZ and WAZ. Sex did not modify these associations. CONCLUSIONS:Higher HAP exposure, as indexed by prenatal CO during critical developmental windows may contribute substantially to long-term poor linear growth throughout childhood.

Household air pollution (HAP) has been associated with adverse pregnancy and birth outcomes, but the underlying mechanisms remain unclear. Pollutants can cross the placenta, potentially causing dysregulation of the crucial organ. Placental microRNAs (miRNAs) may serve as biomarkers of placental health, but studies of prenatal air pollutant exposure and placental miRNAs using non-targeted approaches have been scarce. We leveraged personal air monitoring data from mothers enrolled in the Ghana Randomized Air Pollution and Health Study to estimate prenatal exposure levels to carbon monoxide (CO) and particulate matter <2.5 µm (PM2.5). Placental tissue small RNA was sequenced and aligned to miRbase v22. We used sparse principal components analyses (sPCAs) to identify candidate placental miRNAs associated with prenatal CO (N = 133) and PM2.5 (N = 85) exposure. Associations between candidate miRNAs and prenatal exposures were assessed using linear regressions. We identified four placental miRNAs upregulated with prenatal CO exposure (miR-128-3p, miR-423-3p, miR-671-3p, and miR-744-5p) and five downregulated miRNAs (miR-29b-3p, miR-30e-5p, miR-101-3p, miR-130a-3p, and miR-376b-3p) at P < 0.1. Among female infants only, five miRNAs were downregulated (miR-101-3p, miR-130a-3p, miR-19b-3p, miR-106b-5p, and miR-301a-3p) and one upregulated (miR-22-3) with CO exposure (P < 0.1). We did not identify any associations between placental miRNAs and prenatal PM2.5 exposure. Our results support associations of prenatal CO exposure with differential expressions of critical placental miRNAs that have been implicated in placental disorders by previous studies. This is the first study to examine associations of these exposures with placental miRNAs using a non-candidate approach and lays the groundwork for targeted studies of placental miRNAs associated with prenatal HAP exposure.

Previous studies - primarily in high income countries - have shown that high prenatal temperatures are associated with adverse birth outcomes. However, these studies are mostly focused on average exposure across the full gestational period or short-term exposure immediately prior to delivery and may miss important sensitive windows of exposure in utero. Further, nearly all use ambient air temperature data, which neglect physiologically important interactions between air temperature and humidity. The Ghana Randomized Air Pollution and Health Study (GRAPHS) recruited pregnant individuals from 2013 to 2015 from communities in the Kintampo North Municipality and Kintampo South District of Ghana. We estimated daily maximum shaded wet bulb globe temperature (WBGTmax) and heat index (HImax) during pregnancy and examined associations with birth weight, birth length, head circumference, and incidence of low birth weight, preterm birth, and small for gestational age. Using linear regression analyses, trimester average models identified that higher WBGTmax in the first trimester was associated with larger head circumference; second trimester was associated with shorter birth length, lower birth weight and higher odds of preterm birth, and third trimester was associated with shorter gestational age and larger head circumference. Time-varying analyses using distributed lag nonlinear models find that, compared to the median, lower WBGTmax and HImax (25th percentile) during the first half of pregnancy was associated with higher birth weight and longer birth length. Compared to the median, lower WBGTmax and HImax (25th percentile) in the second half of pregnancy was associated with smaller head circumference while higher wet bulb globe temperature (75th percentile) was associated with larger head circumference. Overall, our study identified that higher WBGTmax and HImax are associated with pregnancy duration and newborn size. Given the overall trend in our study area of rising temperatures, these data suggest that adaptation strategies are urgently needed to protect child health.

Evidence on household air pollution (HAP) and childhood blood pressure (BP) is scarce. We leveraged a prospective pregnancy cohort derived from the Ghana Randomized Air Pollution and Health Study (GRAPHS) to determine associations between cookstove interventions to reduce HAP exposure in the prenatal and first year of life, and BP measured annually from age 4 through 9 years (n = 691). GRAPHS was a randomized-controlled trial of two cookstove interventions-Liquefied Petroleum Gas stove (LPG), improved biomass stove-or Control (three-stone open fire) initiated in early pregnancy and maintained through age one year. We used Poisson and linear mixed-effects models, and Poisson Generalized Estimating Equations to examine associations between stove assignment and high versus normal BP, as determined by BP percentiles for sex, age and height, or secondarily with BP as a continuous outcome. As compared to control, the LPG intervention was associated with lower risk of high Diastolic BP (DBP) [strongest association: age 4-5 (adjusted RR = 0.66; 95 % CI = 0.58, 0.75; unadjusted p < 0.001; Holm-adjusted p < 0.001)], lower risk of having at least one count of high DBP (adjusted RR = 0.86; 95 % CI = 0.78, 0.95, p = 0.002), and lower mean DBP [strongest association: age 4-5 (adjusted β = -1.69; 95 % CI = -2.96, -0.42; unadjusted p = 0.01); Holm-adjusted p = 0.02] compared to control. No associations between improved biomass and BP were identified. These results suggest that an LPG intervention to reduce HAP during prenatal and first year of life is associated with better early to mid-childhood cardiovascular health, highlighting the importance of HAP reduction beginning prenatally.

Rationale: Air pollution exposure, particularly PM2.5, is linked to adverse health outcomes, yet its impact on sleep remains unclear. This study investigates the association between air pollution exposure and sleep-wake patterns in postpartum women using data from the Ghana Randomized Air Pollution and Health Study (GRAPHS). We hypothesize that higher PM2.5 exposure is associated with altered sleep-wake patterns in postpartum women from rural Ghana. Methods: The GRAPHS study enrolled pregnant women from 2013 to 2016. At 4 and 8 years postpartum, participants simultaneously wore personal PM2.5 exposure monitors and actigraphy devices. Personal PM2.5 monitors measured air pollution exposure over a 48-hour period, while actigraphy provided multi-night measures of sleep, including total sleep time (TST, primary outcome), and secondary outcomes including wake after sleep onset (WASO), time in bed (TIB), sleep efficiency, and nighttime awakenings. Sleep intervals were visually identified, and each 30-second epoch was scored as sleep vs wake using the Cole-Kripke algorithm. Linear regression models, adjusted for age, BMI, and household size, were used to assess associations between PM2.5 exposure and sleep outcomes. Results: There were 49 multi-night actigraphy at 4-years postpartum and 78 multi-night actigraphy at 8-years postpartum. On average, participants had mean ages of 33 and 35 years and BMIs of 24.1 and 24.2 at 4 and 8 years postpartum, respectively, with 3.1 nights of actigraphy at 4 years and 2.7 nights at 8 years. Average TST was 6.5 hours at 4 years and 6.0 hours at 8 years postpartum. Sleep onset latency was 18 minutes at 4 years and 4 minutes at 8 years, with WASO times of 81 and 72 minutes, respectively. No associations were identified between average PM2.5 levels over 48 hours and sleep outcomes, including TST, TIB, sleep efficiency, WASO, or number of nighttime awakenings (all p > 0.05). Conclusions: No association was found between average PM2.5 exposure and sleep outcomes, potentially due to limitations in sample size. Future analyses exploring associations with time-varying PM2.5 exposure concentrations may identify time-varying effects on actigraphy-derived sleep metrics that are not identified when averaging PM2.5 exposures. Additionally, incorporating sleep questionnaire responses available for the entire cohort may provide a more comprehensive view of sleep quality in this population. Further studies are needed to investigate objective sleep-wake patterns in relation to air pollution exposure to inform targeted interventions and policies that enhance sleep quality and public health globally.

Background: Household air pollution is a major contributor to cardiovascular disease burden in women in Sub-Saharan Africa. However, little is known about exposures during pregnancy or the effect of clean cooking interventions on postpartum blood pressure trajectories. Methods: The Ghana Randomized Air Pollution and Health Study (GRAPHS) randomized 1414 non-smoking women in the first and second trimesters to liquefied petroleum gas (LPG) or improved biomass stoves – vs control (traditional three-stone open fire). Personal exposure to carbon monoxide was measured at four prenatal timepoints and three times over the first postpartum year. Participants were prospectively followed with annual resting BP measurements at 2, 4, 5, 6, 7, and 8 years postpartum. We employed linear mixed effects models to determine effect of GRAPHS interventions on postpartum BP, and to examine associations between prenatal and postnatal CO and postpartum BP. Results: LPG intervention was associated with 3.54mmHg (95% CI -5.55, -1.53) lower change in systolic BP from enrolment through 8 years postpartum, and 2.27mmHg (95% CI -3.61, -0.93) lower change in diastolic BP from enrolment through 8 years postpartum, as compared to control. In exposure-response analysis, average prenatal CO was positively associated with change in systolic BP from enrolment (β=0.71mmHg, 95% CI 0.08, 1.30, per doubling of CO) Conclusions: LPG cookstove intervention initiated in early pregnancy and maintained through the first postpartum year was associated with lower systolic and diastolic BP trajectories through 8 years postpartum. These findings support the need to integrate clean cooking solutions into existing antenatal care packages. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial Clinical Trial Registration Number: [NCT01335490][1] ### Funding Statement GRAPHS was supported by the National Institute of Environmental Health Sciences (NIEHS) Grants R01 ES019547, R01 ES026991, R01ES034433, P30 ES009089, and P30 ES023515, Fogarty Institute R21 TW010957, NIH Shared Instrument Program S10OD016219, Thrasher Research Fund, and the Clean Cooking Alliance. AGL was additionally supported by the National Heart, Lung and Blood Institute K23 HL135349. The authors and their institutions declare that they did not receive payments from third parties for any aspect of the work presented in this manuscript. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: IRBs of the three collaborating institutions, Kintampo Health Research Centre, Columbia University and Icahn School of Medicine at Mount Sinai I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Anonymized data that underlie the results reported herein are available upon request. Proposals should be directed to kwakupoku. asante@kintampo-hrc.org and to Alison.Lee@mssm.edu; to gain access, data requestors will need to sign a data access agreement [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT01335490&atom=%2Fmedrxiv%2Fearly%2F2025%2F01%2F18%2F2025.01.17.25320752.atom

BACKGROUND:The association between prenatal household air pollution (HAP) exposure and childhood blood pressure (BP) is unknown. OBJECTIVE:Within the Ghana Randomized Air Pollution and Health Study (GRAPHS) we examined time-varying associations between a) maternal prenatal and b) first-year-of-life HAP exposure with BP at 4 years of age and, separately, whether a stove intervention delivered prenatally and continued through the first year of life could improve BP at 4 years of age. METHODS:GRAPHS was a cluster-randomized cookstove intervention trial wherein n=1,414 pregnant women were randomized to one of two stove interventions: a) a liquefied petroleum gas (LPG) stove or improved biomass stove, or b) control (open fire cooking). Maternal HAP exposure over pregnancy and child HAP exposure over the first year of life was quantified by repeated carbon monoxide (CO) measurements; a subset of women (n=368) also performed one prenatal and one postnatal personal fine particulate matter (PM2.5) measurement. Systolic and diastolic BP (SBP and DBP) were measured in n=667 4-y-old children along with their PM2.5 exposure (n=692). We examined the effect of the intervention on resting BP z-scores. We also employed reverse distributed lag models to examine time-varying associations between a) maternal prenatal and b) first-year-of-life HAP exposure and resting BP z-scores. Among those with PM2.5 measures, we examined associations between PM2.5 and resting BP z-scores. Sex-specific effects were considered. RESULTS:Intention-to-treat analyses identified that DBP z-score at 4 years of age was lower among children born in the LPG arm (LPG β=-0.20; 95% CI: -0.36, -0.03) as compared with those in the control arm, and females were most susceptible to the intervention. Higher CO exposure in late gestation was associated with higher SBP and DBP z-score at 4 years of age, whereas higher late-first-year-of-life CO exposure was associated with higher DBP z-score. In the subset with PM2.5 measurements, higher maternal postnatal PM2.5 exposure was associated with higher SBP z-scores. DISCUSSION:These findings suggest that prenatal and first-year-of-life HAP exposure are associated with child BP and support the need for reductions in exposure to HAP, with interventions such as cleaner cooking beginning in pregnancy. https://doi.org/10.1289/EHP13225.

Rationale: The impact of a household air pollution (HAP) stove intervention on child lung function is poorly described. Objectives: To assess the effect of a prenatal to age one HAP stove intervention on, and exposure-response associations with, age four lung function. Methods: The Ghana Randomized Air Pollution and Health Study (GRAPHS) randomized pregnant women to a liquefied petroleum gas (LPG), improved biomass, or open fire (control) stove through child age one. We quantified HAP exposure by repeated maternal and child personal carbon monoxide (CO) exposure measurements. Children performed oscillometry, an effort-independent lung function measurement, at age four. We examined associations between GRAPHS stove assignment and prenatal and infant CO measurements and oscillometry via generalized linear regression models. We used reverse distributed lag models (rDLMs) to examine time-varying associations between prenatal CO and oscillometry. Measurements and Main Results: The primary oscillometry measure was reactance at 5 Hertz, X5, a measure of elastic and inertial lung properties. Secondary measures included total, large and small airway resistance (R5, R20, R5-20), area of reactance (AX) and resonant frequency (Fres). Of the 683 children who attended the lung function visit, 567 (83%) performed acceptable oscillometry. Two hundred and twenty-one, 106, and 240 children were from the LPG, improved biomass and control arms, respectively. Compared to control, the improved biomass stove was associated with lower reactance at 5 Hertz (X5 z-score, beta=-0.25, 95% CI -0.39, -0.11), higher large airway resistance (R20 z-score, beta=0.34, 95% CI 0.23, 0.44) and higher area of reactance (AX z-score, beta=0.16, 95% CI 0.06, 0.26) suggestive of overall worse lung function. The LPG stove was associated with higher X5 (beta=0.16, 95% CI 0.01, 0.31) and lower small airway resistance (R5-20 z-score, beta=-0.15, 95% CI -0.30, 0.0) suggestive of better small airway function. Higher average prenatal CO exposure was associated with higher R5 and R20 and DLMs identified sensitive windows of exposure between CO and X5, R5, R20 and R5-20. Conclusions: These data support the importance of prenatal HAP exposure on child lung function. Clinical trial registration available at www.clinicaltrials.gov, ID: NCT01335490.

BACKGROUND AND AIM: Climate change is increasing exposures to higher ambient temperatures, particularly in rural developing communities where people have limited access to indoor cooling. We aimed to examine associations between prenatal heat and birth outcomes in rural Ghana. METHOD: We leveraged the Ghana Randomized Air Pollution and Health Study (GRAPHS) prenatal cohort recruited from 35 rural communities in the Bono East Region of Ghana between 2013-2015. We assigned prenatal heat stress from conception to delivery using weekly averages of satellite-derived daily Wet Bulb Globe Temperature (WBGT) estimates corresponding to the community of each participant. We performed multivariable regression with average WBGT over pregnancy and trimester (TM) specific averages included in the same model to understand associations with birth weight, length, head circumference, and small-for-gestational-age (SGA). RESULTS: 1,173 pregnant individuals with delivery 28 weeks were available for analysis. Weekly prenatal WBGT averages in the cohort ranged from 22.7-30.8°C. Extreme heat events (WBGT 30°C) have been occurring with increasing frequency and 82% of the participants experienced 1 extreme heat event in pregnancy. Higher average WBGT in the second TM was associated with lower mean birth weight (β = -36.5 g, 95% CI: -72.9, -0.2) and birth length (β = -0.32 cm, 95% CI: -0.61, -0.02) with third TM exposure suggestive of reductions, although not reaching statistical significance. Higher average WBGT across gestation, and in first and third TMs, were associated with increased head circumference, possibly a head sparing effect. No significant associations with SGA or LBW were identified. CONCLUSIONS: We demonstrate impacts of heat stress on newborn anthropometrics in this rural Ghanaian population where the range of temperatures is relatively narrow. Given the link between size at birth and future disease, it is critical to better understand how rising global temperatures impacts newborn health, and more importantly, identify interventions to mitigate these effects.

Background Personal exposure to fine particulate matter (PM 2.5 ) from household air pollution is well-documented in sub-Saharan Africa, but spatiotemporal patterns of exposure are poorly characterized. Objective We used paired GPS and personal PM 2.5 data to evaluate changes in exposure across location-time environments (e.g., household and community, during cooking and non-cooking hours), building density and proximity to roadways. Methods Our study included 259 sessions of geolocated, gravimetrically-calibrated one-minute personal PM 2.5 measurements from participants in the GRAPHS Child Lung Function Study. The household vicinity was defined using a 50-meter buffer around participants’ homes. Community boundaries were developed using a spatial clustering algorithm applied to an open-source dataset of building footprints in Africa. For each GPS location, we estimated building density (500 m buffer) and proximity to roadways (100 m buffer). We estimated changes in PM 2.5 exposure by location (household, community), time of day (morning/evening cooking hours, night), building density, and proximity to roadways using linear mixed effect models. Results Relative to nighttime household exposure, PM 2.5 exposure during evening cooking hours was 2.84 (95%CI = 2.70–2.98) and 1.80 (95%CI = 1.54–2.10) times higher in the household and community, respectively. Exposures were elevated in areas with the highest versus lowest quartile of building density (Factor Q1vsQ4 = 1.60, 95%CI = 1.42–1.80). The effect of building density was strongest during evening cooking hours, and influenced levels in both the household and community (31% and 65% relative increase from Q1 to Q4, respectively). Being proximal to a trunk, tertiary or track roadway increased exposure by a factor of 1.16 (95%CI = 1.07–1.25), 1.68 (95%CI = 1.45–1.95) and 1.27 (95%CI = 1.06–1.53), respectively. Impact Household air pollution from cooking with solid fuels in sub-Saharan Africa is a major environmental concern for maternal and child health. Our study advances previous knowledge by quantifying the impact of household cooking activities on air pollution levels in the community, and identifying two geographic features, building density and roadways, that contribute to maternal and child daily exposure. Household cooking contributes to higher air pollution levels in the community especially in areas with greater building density. Findings underscore the need for equitable clean household energy transitions that reach entire communities to reduce health risks from household and outdoor air pollution.

The Harmattan season (December to March) in Western Africa is characterized by dry, dusty winds blowing from the Saharan desert towards the Gulf of Guinea, resulting in higher fine particulate matter (PM2.5) exposure; however, associations with birth size are unknown. We leveraged this seasonal variability in exposure to identify whether there are critical windows during pregnancy to Harmattan that negatively impact newborn size in a Ghanaian pregnancy cohort. The Ghana Randomized Air Pollution and Health Study (GRAPHS) enrolled 1,414 pregnant women from Kintampo, Ghana. Gestational age (GA) was established by ultrasound at enrollment; birth weight, length and head circumference were measured using standardized protocols and digital scales. We employed distributed lag models (DLMs) to examine time-varying associations between prenatal exposure to the Harmattan (yes/no) for each week gestation and birth weight, length and head circumference among infants born live > 37 weeks. DLMs also estimated cumulative effects over gestation. Models were adjusted for maternal age, parity, infant sex, ethnicity, asset index and number of antenatal visits. Analyses included n=1261 mother-infant pairs. Harmattan exposure from 3-7, 18-29, and 38-40 weeks' gestation (Figure, panel A) was associated with lower birth weight with a cumulative effect of Harmattan over gestation on birth weight of -714 grams (95% CI -1159, -268). Separately, Harmattan exposure from 4-12 and 23-31 weeks' gestation (Figure, panel B) was associated with smaller head circumference with a cumulative effect of Harmattan over gestation on head circumference of -2.9 centimeters (95% CI -5.3, -0.5). We did not identify an association between Harmattan and birth length. These data suggest that prenatal Harmattan exposure is associated with lower birth weight and smaller head circumference. Certain gestational windows may have greater impact than others. Climate change threatens to make Harmattan more severe lending urgency to better understanding its effects on health beginning in utero.

Pyrethroid pesticides are widely used in sub-Saharan Africa for malaria vector control, as the predominant insecticide in treated bednets, or as a chemical during indoor residual spraying campaigns. In non-malarious areas, prenatal pyrethroid exposure has been negatively associated with newborn size, although effect sizes have been typically small, and results inconsistent. We aimed to evaluate the association of urinary prenatal pyrethroid concentrations on newborn size in an area where malaria is endemic and accounts for significant reductions in birth size. Within a prospective Ghanaian prenatal cohort (GRAPHS), we measured pyrethroid insecticide metabolites in repeated urine samples across pregnancy. With multivariable linear regression, we examined associations between creatinine-corrected pyrethroid metabolite concentrations averaged over pregnancy and birth weight, length, and head circumference and examined effect modification by placental malaria. Models were adjusted for other pesticide co-exposures (organophosphate, herbicide metabolites) and other potential confounders such as parity, BMI, wealth, and cook smoke exposure. Among samples from 1,152 pregnant GRAPHS participants, 90% had detectable 3-phenoxybenzoic acid, OPM, a metabolite of pyrethroids commonly used for malaria control (permethrin, cypermethrin, deltamethrin). Median OPM prenatal exposure was 0.36 μg/mL (IQR 0.17, 0.84). A doubling of OPM was associated with a -19.1 gram (95% CI: -39.7, 1.4) decrease in birth weight. Among participants who had placental malaria, a doubling of OPM was associated with a -0.6 cm (95% CI: -0.9, -0.3) decrease in birth length. No association between OPM and head circumference was identified. Pyrethroids are negatively associated with infant size at birth, even in a malarious area where use is aimed at reducing the incidence of pregnancy malaria. This finding, along with increasing pyrethroid resistance among Anopheles mosquitoes, underscores the imperative to identify and test alternative malaria control strategies for use in pregnancy.

A major part of Ghana's current household energy policy is focused on using a branded cylinder recirculation model (BCRM) to promote the safe use of Liquefied Petroleum Gas (LPG) for primary cooking. The implementation of the BCRM is expected to increase LPG adoption by households to the announced policy goal of 50% of the population by 2030. We investigated the impact of the COVID-19 pandemic on the implementation of the BCRM, availability, and household use of cleaner fuels. This was assessed using existing data on clean fuel use prior to the COVID-19 pandemic. Additional data was collected using questionnaire-based household surveys and qualitative interviews. It was found that the expansion of BCRM was significantly impacted by the COVID-19 pandemic. Planning activities such as baseline data collection and stakeholder engagement were delayed due to the COVID-19 restrictions. Changes in household incomes during the pandemic had the biggest percentage effect on household choice of cooking fuel, causing a regression in some cases, to polluting fuel use. This study provides insights that could be valuable in future understanding of the interactions between pandemic control measures and economic disruptions that may affect household energy choices for cooking.

BACKGROUND:Prenatal household air pollution impairs birth weight and increases pneumonia risk however time-varying associations have not been elucidated and may have implications for the timing of public health interventions. METHODS:The Ghana Randomized Air Pollution and Health Study (GRAPHS) enrolled 1,414 pregnant women from Kintampo, Ghana and measured personal carbon monoxide (CO) exposure four times over pregnancy. Birth weight was measured within 72-hours of birth. Fieldworkers performed weekly pneumonia surveillance and referred sick children to study physicians. The primary pneumonia outcome was one or more physician-diagnosed severe pneumonia episode in the first year of life. We employed reverse distributed lag models to examine time-varying associations between prenatal CO exposure and birth weight and infant pneumonia risk. RESULTS:Analyses included n = 1,196 mother-infant pairs. In models adjusting for child sex; maternal age, body mass index (BMI), ethnicity and parity at enrollment; household wealth index; number of antenatal visits; and evidence of placental malaria, prenatal CO exposures from 15 to 20 weeks gestation were inversely associated with birth weight. Sex-stratified models identified a similar sensitive window in males and a window at 10-weeks gestation in females. In models adjusting for child sex, maternal age, BMI and ethnicity, household wealth index, gestational age at delivery and average postnatal child CO exposure, CO exposure during 34-39 weeks gestation were positively associated with severe pneumonia risk, especially in females. CONCLUSIONS:Household air pollution exposures in mid- and late- gestation are associated with lower birth weight and higher pneumonia risk, respectively. These findings support the urgent need for deployment of clean fuel stove interventions beginning in early pregnancy.