Hello Thank you for trusting HCM Normal sperm have an oval head with a long tail. Abnormal sperm have head or tail defects — such as a large or misshapen head or a crooked or double tail. These defects might affect the ability of the sperm to reach and penetrate an egg. However, having a large percentage of misshapen sperm isn t uncommon. In addition, morphology alone doesn t indicate if you are fertile or not. A typical semen analysis also assesses: Semen volume Total sperm number Sperm concentration Vitality (percent alive) Movement (motility) Coiling and bending of the tail are sometimes seen. Broken tails of less than half normal length should be categorized abnormal. Double, triple and quadruple tails are seen and are abnormal. Cytoplasmic droplets along the tail may indicate an immature sperm . if tail defect more decrease sperm motility so decrease fertilization capacity. Please consult your doctor further guidance.