The effect of possible mediators on the association between chewing khat during pregnancy and fetal growth and newborn size at birth in Eastern Ethiopia
Authors: Wondemagegn Amsalu Taye , Bekana Miressa , Bekuretsion Yonas , Afework Mekbeb 
Published: January 2024

Abstract
Introduction
Restriction in the growth of the fetus is a leading cause of stillbirth, neonatal mortality, and short- and long-term morbidity. Documented existing scientific evidence have shown the effects of maternal drugs use, alcohol drinking, tobacco smoking, cocaine use and heroin use on fetal growth restriction. However, data is lacking on the effects of khat chewing during pregnancy on fetal growth status and newborn size at birth. Therefore, the aim of the present study was to measure the effect of chewing khat during pregnancy on fetal growth and size at birth in eastern Ethiopia.

Method
A cohort study was conducted in selected health institutions in eastern Ethiopia. All pregnant women fulfilled the eligibility criteria in the selected health institutions was the source population. The calculated sample size of exposed and unexposed groups included in the study, in total, was 344. Data collection was performed prospectively by interviewers administered questionnaires, and anthropometric, clinical and ultrasound measurements. Data was analyzed using SPSS version 27 and STATA version 16 software. The survival analysis (cox proportional hazards model) and generalized linear model (GLM) for the binomial family analysis were performed to estimate the crude and adjusted relative risk and attributable risk (AR) with corresponding 95% CI of chewing khat on fetal growth restriction. The mediation effect has been examined through Generalized Structural Equation Modeling (GSEM) analysis using the Stata ‘gsem’ command. Statistically significant association was declared at p-value less than 5%.

Results
In the present study, the incidence of fetal growth restriction (FGR) among the study cohorts was 95 (29.7%); of this, 81 (85.3%) were among khat chewer cohorts. The relative risk of fetal growth restriction among khat chewer cohort mothers was significantly higher (aRR = 4.32; 95%CI 2.62–7.12). Moreover, the incidence of small for gestational age at birth among the present study cohorts was 100 (31.3%); 84 (84%) were from khat chewer cohorts’ deliveries. More importantly, in the present study, 98.95% of the ultrasound-identified fetuses with FGR were found to be SGA at birth. Hence, in the current study, FGR was highly associated with SGA at birth. In additional analysis, the regression coefficient of khat chewing during pregnancy on fetal growth restriction has been decreased in size from path o, β = 0.43, p < 0.001 to path o’, β = 0.32, p < 0.001, after adjusting for gestational hypertension and maternal anemia.

Conclusion
In sum, the present study showed khat chewing during pregnancy is not simply affected the mothers, but it also affected the unborn fetuses. Therefore, the health workers as well as the local community and religious leaders should give high emphasis on provision of health education regarding the damage of chewing khat by pregnant mothers, with especial focus of the effects on their fetuses.