Purpose: This study aims to explore the higher education expansion phenomenon and to what extent that expansion could reshape the pattern of gender. Design/methodology/approach: We selected Taiwan's higher education as a research target. First, we describe the gender diversity patterns in the humanity, social science and STEM programs according to Trow's definition. Second, we identify discrepancies in gender in the major programs according to different indices. Becker's "D," Blau index, GPI, trend analysis and multiple comparisons were used to transform the comparison series data. Findings: First, to assess system-wide gender diversity, it was shown that in the elite stage, the "D" is more sensitive than the Blau index in plotting trends. Second, neither the "D" nor the Blau index showed sensitivity in humanity and social science programs in the post-mass stage. Third, the GPI more accurately detects differences in gender patterns in the mass and universal stages. Practical implications: This study illuminates gender diversity patterns with indices transformation in higher education. Considering higher education expansion is a global phenomenon, the fitted indices can be used to detect gender diversity issues in wider higher education settings. Originality/value: This study provides an example for addressing the issue using different indices to identify previous and future trends in the higher education system. The study suggests alternative interpretations for gender diversity in various programs that will assist in modifying related gender policies in higher education.