Introduction: Pelvic congestion syndrome (PCS) may be effectively managed with conservative treatment in certain patients. Treatment with venoactive drugs is common, but supportive data are limited. This study evaluated the clinical efficacy of micronized purified flavonoid fraction (MPFF) in women with PCS. Methods: In a single-blind, placebo-controlled study, women with duplex ultrasound diagnosis of pelvic varicose veins (PVV) and PCS were randomized to MPFF 1000 mg once daily or placebo for 2 months. Clinical manifestations of PCS were evaluated at baseline and end of treatment (M2) using three assessment tools: disease-specific quality of life (QoL) Pelvic Varicose Vein Questionnaire (PVVQ), Pelvic Venous Clinical Severity Score (PVCSS), and the Visual Analog Scale (VAS) for the main symptoms of the disease.