Men's Screening Tests Slideshow Impotence (ED) Slideshow Pictures Take the Low Testosterone (Low T) Quiz Seminal vesicle: One of two structures that are about 5 cm long and are located behind the bladder and above the prostate gland. The seminal vesicles contribute fluid to the ejaculate. From Men's Health Resources Tips for Taking Your HIV MedicinesChronic Myleogenous Leukemia Phases and TreatmentDo You Have Symptoms of Hearing Loss? Featured Centers When Prostate Cancer SpreadsEssential Tips to Manage DiabetesWhat Is Cystic Fibrosis? What Causes It? Health Solutions From Our Sponsors Kept Your Wisdom Teeth? What is TAVR?