Abstract for: A Dynamic Model of Circadian Rhythm of Melatonin and the Effect of Night Shifts on Risk of Autism in Late-Stage Pregnancy

Maternal melatonin production and melatonin circadian rhythm are disrupted by light exposure during the night due to night shift work, which affects fetal brain development. The study aims to model the dynamic effects and causal interactions of disruption of the melatonin rhythm of a pregnant woman working the night shift on the melatonin and malondialdehyde rhythms of the fetus and the risk of autism in the fetus. A simulation model of maternal-fetal circadian rhythm disruption and its impact on autism risk is constructed. The system boundaries of the problem suggest two interconnected subsystems: the maternal-fetal melatonin circadian rhythms and the maternal-fetal MDA (oxidative stress) circadian rhythms. Healthy maternal circadian and disrupted maternal circadian patterns (due to night shift work) are determined, and interactions between maternal and fetal variables are defined based on the literature. In scenario analysis, different night shift work conditions are simulated. The risk of autism in the fetus increased as a result of night shifts, and even if the night shift was stopped after a certain period, the risk of autism decreased but did not decrease to the base level. The study can provide a different dynamic perspective on protecting fetal health and developing work-shift-related actions to prevent neurodevelopmental disorders like autism. The impacts of circadian disorders should be examined in more detail, and further clinical studies should be conducted on fetal health.