This research aims to assess the associations between oral contraceptive (OC) use and endocrine and metabolic health by leveraging biomarker data and female health survey responses. This study will focus on three objectives:
(i) Endocrine Biomarker Analysis: To evaluate differences in key endocrine-related biomarkers, including lipid profiles and nutrient markers, between women with OC use (stratified by duration) and never-users. This analysis will explore associations between OC use and risk factors for conditions such as hypothyroidism and hyperlipidemia, which have been independently associated with OC use and duration of use.
Rationale: Long-term OC use is associated with nutrient deficiencies, thyroid dysfunction, and hyperlipidemia. Identifying endocrine biomarker patterns could elucidate pathways through which OC use affects metabolic and endocrine health.
(ii) Gut Microbiome Analysis: To investigate the gut microbial diversity and composition differences between OC users (stratified by duration) and never-users. Microbiome measures such as alpha diversity (Shannon, Simpson) and beta diversity (Bray-Curtis, UniFrac) will identify microbial pathways influencing lipid metabolism, nutrient absorption, and endocrine health.
Rationale: Evidence increasingly suggests that hormonal contraceptives may alter gut microbial composition. The gut microbiome plays a critical role in regulating bile acids, cholesterol metabolism, and nutrient absorption. Hormonal contraceptives may induce dysbiosis, indirectly affecting metabolic and endocrine pathways.
(ii) Pathway Analysis: Using structural equation modeling (SEM), the study will explore direct and indirect relationships between OC use, microbiome changes, and endocrine biomarkers.
Rationale: SEM offers a comprehensive understanding of how OC use influences endocrine biomarkers and microbiome changes directly and indirectly, which traditional regression approaches cannot fully capture.