Meconium-stained amniotic fluid as a protective factor against childhood dermatitis and skin rash-related hospitalization in the offspring – a population-based cohort analysis

Background: Gut microbiome influences cutaneous diseases including atopic dermatitis. Possible impact of intrauterine exposure to meconium on the occurrence of dermatitis and skin rash was proposed. Objective: We investigated the possible influence of intrauterine exposure to meconium-stained amniotic fluid (MSAF) on the occurrence of dermatitis and skin rash-related hospitalizations throughout childhood. Methods: Singleton deliveries occurring between 1991 and 2014 at a single medical centre were divided into two study groups based on presence or lack of MSAF during delivery. Population-based cohort analysis, Kaplan–Meier survival analysis and Cox proportional hazards model were used to study the association between MSAF and cutaneous morbidity-related hospitalizations. Results: A lower rate of the total dermatitis or skin eruption-related hospitalization was documented in the MSAF-exposed group; 0.78 per 1000-person years (0.9%, n = 312), as compared to 0.98 per 1000-person years in the unexposed group (1.0%, n = 1992) with a hazard ratio of 0.86 (95% CI 0.76-0.96, P = 0.011). The survival curve showed lower cumulative hospitalization rate in the MSAF-exposed group as compared to the unexposed group (log rank P = 0.01). The Cox analysis, controlled for confounders, demonstrated MSAF exposure to be an independent protective factor for dermatitis and skin rash-related hospitalizations during childhood (adjusted HR 0.878 (95% CI 0.779-0.990, P = 0.034). Conclusion: Fetal exposure to MSAF appears to be an independent protective factor for dermatitis and skin rash-related hospitalizations in the offspring throughout childhood and adolescence.