Purpose <p>Polycystic ovary syndrome (PCOS) is characterized by androgen excess and ovulatory dysfunction and appears to be associated with alterations in muscle mass and function. The study aims to investigate whether oral contraceptive (OC) use affects muscle mass and strength in women with PCOS.</p> Methods <p>Twenty women with PCOS (median age 20.5 years and BMI 26.1 kg/m²) and 20 age- and BMI-matched healthy controls were included. Clinical, hormonal, and biochemical assessments were conducted along with body composition analyses using magnetic resonance imaging (MRI) proton density fat fraction (PDFF%) and muscular strength assessment by isokinetic dynamometry. In women with PCOS, measurements were repeated after at least three cycles of OC therapy.</p> Results <p>At baseline, women with PCOS exhibited significantly higher levels of total testosterone, free androgen index (FAI), and homeostasis model assessment of insulin resistance (HOMA-IR) levels compared to healthy controls (<i>p</i> &lt; 0.001, <i>p</i> = 0.001, <i>p</i> = 0.004, respectively). PCOS group also showed significantly higher average power (AvP) of knee extensors at 60°/sec (<i>p</i> = 0.002). AvP correlated positively with total testosterone and FAI levels in the whole study group (r = 0.450, <i>p</i> = 0.004, r = 0.318, <i>p</i> = 0.045, respectively). Following OC therapy, testosterone levels and FAI decreased (<i>p</i> = 0.02 and <i>p</i> &lt; 0.001, respectively); whereas thigh muscle mass or lower limb strength remained unchanged.</p> Conclusions <p>Short-term OC use in women with PCOS led to a reduction in androgen excess without measurable effects on muscle composition or strength. These findings suggest that muscle function and composition remain stable over the short term, despite hormonal modulation. Further research is required to understand how long-term management strategies for PCOS might affect muscle mass and function.</p>