Chlamydia infection is very common among young adults and teenagers. However, many people do not know that they have chlamydia, because although they are infected, they may not have any symptoms. About 75% of infected women and half of infected men have no symptoms of chlamydia.
Normally its caused by multiple sex partners or lack of contraceptive usage.
Chlamydia can cause early labor and delivery and can be passed from mother to baby during birth. Chlamydia infection in newborns can cause neonatal conjunctivitis (an infection of the baby's eyes) and pneumonia. Without prompt medical treatment, the infant's eyes can be seriously and permanently damaged.
I believe treatment of this in pregnancy would either be erythromycin or amoxicillin.
If chlamydia's left untreated yes, it could cause infetility. Its probably best for you to ask your husband to be tested as well coz if you got it from him there's a chance that he could pass it again on you.
During treatment you're not supposed to have sexual intercourse.
Hth and good luck on your pregnancy