Background Geophagy is an ancestral practice particularly found among African women who describe beneficial effects on the sympathetic signs of pregnancy. Studies have reported a significant prevalence of consumption of kaolin, known as geophagy, within migrant population. However, this behavior, like other environmental factors, could lead to obstetrical and neonatal risks. Objective The objective of our study was to evaluate the obstetrical and neonatal impact of kaolin consumption, especially on Z-SCORE for weight-for-gestational age in the newborn. Methods This mono-centric historical cohort study was carried out on the basis of questionnaires and patients' obstetrical records. It was conducted between January 1 and July 1, 2017. Patients were divided into two groups: 1) women who consumed kaolin (at least once during their pregnancy), and 2) women who did not consume kaolin. Morphometric characteristics of the newborn were retrieved in obstetrical records. Results Results: 105 pregnant women were included: 26 exposed and 79 non exposed. Women who consumed kaolin were more frequently without social protection at their first consultation (p < .01). Multivariate analysis did not show a significant association between Z-SCORE for weight-for gestational age in the newborn and kaolin consumption (beta = 0.13, p = .54) after adjusting on age, precariousness, BMI, intake of toxic substances, anemia and beginning eclampsia. Among these covariates, precariousness was significantly associated with both a decrease in Z-SCORE for weight (beta = -0.87, p < .002) and size (beta = -0.68, p < .01). Conclusion Geophagy is not to be neglected in socially advantaged countries due to increased immigration. This study found no association between kaolin consumption and birth weight. However, there was a correlation between precariousness and low birth weight which reinforces the importance of tightening the follow-up during pregnancies in the most precarious women.