 [ Symptoms ] what is chlamydia [ Disease ] chlamydia say kluh mid ee uh is an infection spread through sexual contact this disease infects the urethra in men in women it infects the urethra and the cervix and can spread to the reproductive organs it is one of the most common sexually transmitted diseases  stds  chlamydia does not cause problems if you treat it right away but left untreated it can lead to serious problems especially for women if it spreads it can cause pelvic inflammatory disease this serious infection can make it hard or impossible for a woman to get pregnant pregnant women who have chlamydia often pass it to their babies at birth if the infection gets in a baby is eyes it can cause blindness they can also have other problems like pneumonia pneumonia can be deadly in a newborn having chlamydia makes a person more likely to get hiv from someone who is infected with hiv hiv is the virus that causes aids webmd medical reference from healthwise this information is not intended to replace the advice of a doctor healthwise disclaims any liability for the decisions you make based on this information © 1995 2011 healthwise incorporated healthwise healthwise for every health decision and the healthwise logo are trademarks of healthwise incorporated