Sexually Transmitted Infections (STIs) are the infections that commonly spread by sexual activity. There are no initial symptoms of sexually transmitted infections, which increase the risk of passing the infections to others. The signs and symptoms of these infections comprise of pelvic pain, ulcers around the genitals, and vaginal and penile discharge. Many different types of parasites, bacteria and viruses can be transmitted sexually. Trichomoniasis is an example of a parasitic STI. Bacterial sexually transmitted infections include gonorrhea, syphilis and chlamydia. HIV/AIDS, genital herpes and genital warts are viral STIs. Some sexually transmitted infections can spread by non-sexual contacts such as breastfeeding, during childbirth, and contact with the donor tissue and blood. The objective of this book is to give a general view of the sexually transmitted infections. It provides significant information on these infections to help develop a good understanding. This book is a vital tool for all researching and studying this field.