Molar Incisor Hypomineralization (MIH) is a developmental enamel defect that affects permanent first molars (PFMs) and incisors, leading to caries and early tooth loss. This systematic review investigates the literature for the relationship between stress-related factors and the occurrence of MIH. A comprehensive literature search was conducted across PubMed, Cochrane, Scopus, Google Scholar, and BASE. Articles were screened and data extracted using the Rayyan platform for systematic reviews. The quality of the included studies was assessed using the Newcastle–Ottawa Scale (NOS). Six-studies were included, five examined maternal stress during pregnancy while one on stress experienced during early childhood. Out of them, five reported a significant association between stress and MIH. Given the significant variability in stress assessment methods across studies, we were able to include only two studies in the meta-analysis. Although not statistically significant, the meta-analysis showed a tendency for increased odds of MIH in the presence of stress, with an overall odds ratio of 1.46 (95% CI: 0.66–3.22). These findings suggest a potential association between psychological stress and MIH. However, further research is needed to confirm these results and elucidate the mechanisms involved. Addressing current research limitations will improve study reliability and inform preventive strategies to reduce maternal and early childhood stress, potentially mitigating MIH prevalence.