Menstruation, periodic discharge from the vagina of blood, secretions, and disintegrating mucous membrane that had lined the uterus. 1  The biological significance of the process in humans can best be explained by reference to the reproductive function in other mammals.
Chlamydial (kla-MID-ee-al) infections are caused by three species of microorganisms. Chlamydia trachomatis can cause eye or lung infections and can also infect the urinary and genital areas of both men and women. Chlamydia pneumoniae causes infections of the respiratory tract, and Chlamydia psittaci causes an illness, known as parrot fever, that is similar to the flu.
Chlamydia trachomatis is a bacteria, which is found in the semen and vaginal fluids of men and women who have the infection.Chlamydia is easily passed from one person to another through sexual contact. Anyone who is sexually active can get it and pass it on. You donât need to have lots of sexual partners. In women, chlamydia can spread to other reproductive organs causing pelvic inflammatory disease (PID). 2  This can lead to long-term pelvic pain, blocked fallopian tubes, infertility and ectopic pregnancy (when the pregnancy develops outside the uterus, usually in a fallopian tube).