Serum thyroid-stimulating hormone and sexual self-schema in domain-specific female sexual function: a cross-sectional study.

Introduction: Female sexual dysfunction (FSD) is multifactorial, and thyroid status and sexual self-schema (SSS) may contribute differently across domains of sexual function. The aim of this study was to examine whether serum thyroid-stimulating hormone (TSH) and SSS are independently associated with domain-specific female sexual function. Methods: This cross-sectional study included 200 sexually active women aged 18-60 years attending a gynecology outpatient clinic between October 2025 and February 2026. Participants completed the Female Sexual Function Index (FSFI) and the SSS Scale. Morning fasting serum TSH was measured with a chemiluminescent immunoassay and clinical threshold was 4 mIU/L. Group comparisons were performed between women with and without FSD defined by a FSFI total score of ≤26.55. Spearman correlations were calculated and adjusted for multiple comparisons using false discovery rate (FDR) correction. Multivariable linear regression models were constructed for FSFI domains and total score, adjusting for age, education, TSH, and SSS. A sensitivity analysis additionally adjusted the arousal model for comorbid hypothyroidism. Results: Primary outcomes were domain-specific FSFI domains and total score. Female sexual dysfunction was present in 116 of 200 women (58%). Mean TSH did not differ between women with and without FSD. Thyroid-stimulating hormone was negatively correlated with arousal and was not correlated with other domains or total score. Sexual self-schema was associated with desire, arousal, satisfaction, pain, and total score after FDR correction. In multivariable models, higher TSH was independently associated with lower arousal score. Sexual self-schema was independently associated with desire and satisfaction. When TSH was modeled categorically, high TSH remained associated with lower arousal. The TSH-arousal association remained significant after additionally adjusting for comorbid hypothyroidism, which was not independently associated with arousal. Discussion: In women reporting arousal difficulties, TSH may be clinically relevant even when overall sexual function is not impaired. Strengths of this study include domain-specific modeling, structured exclusion of psychiatric disorders, and evaluation of endocrine and cognitive factors in the same framework. Limitations include cross-sectional design, single TSH measurement without free thyroid hormones or antibodies, reliance on self-report outcomes, and limited representation of overt thyroid disease. Taken together, these findings suggest higher TSH was independently associated with lower sexual arousal, while SSS showed broader associations with desire and satisfaction, supporting a domain-specific biopsychosocial model of female sexual function.