Unlike many other industries, which are characterized by a more significant presence of men than women, the healthcare sector has a clear majority of women. However, even if at the non-executive level, the percentage of women is extremely higher than that of men, at the executive level, this percentage is completely overturned, generating the so-called glass ceiling effect. Despite extensive research on gender diversity and its impact on financial metrics, few studies have focused on clinical measures. To bridge this research gap, the article analyzes the relationship between gender diversity and healthcare metrics. We developed an econometric model for unbalanced panel data by performing a random effect and a quantile regression analysis, which test the relationship between gender diversity and the average length of stay (LOS), controlling for structural and clinical metrics. We find that, in general, a higher percentage of women in non-executive positions is related to an increase in LOS. Conversely, a higher rate of women in executive positions is related to a lower level of LOS. Empirical evidence supports the relevance of including human resources strategies to increase the number of women at executive managerial positions. However, the study highlights also the necessity to consider how to make the public health sector positions more appealing for men.