Women and Chlamydia

Medically Reviewed by Louise Chang, MD on May 06, 2011
5 min read

You might not be intimately familiar with the name, but chlamydia is actually the most commonly reported bacterial sexually transmitted disease (STD) in the U.S. Each year, about 1.2 million infections are reported to the Centers for Disease Control and Prevention (CDC). But because chlamydia often has no symptoms, at least as many people could be living with the disease without even realizing it.

To help young women protect themselves against this highly preventable STD, WebMD asked Sami Gottlieb, MD, MSPH, medical officer in the CDC's Division of STD Prevention, to walk readers through the basics of Chlamydia. She shares why this STD is so risky for women, and offers important advice on how to avoid getting infected.

What exactly is chlamydia?

Chlamydia is a sexually transmitted infection caused by the bacterium Chlamydia trachomatis. It's passed from person to person through sex, and it can cause a wide variety of complications if it's not treated.

What kinds of health problems can chlamydia cause?

The main complication that can result from untreated chlamydia infections is infertility in women, and that's the thing that we're most worried about. Usually in women, chlamydia infects the cervix, which is the opening to the uterus. But if it's not treated, it can travel up into the upper genital tract—the uterus, the fallopian tubes, the ovaries. And sometimes it causes a condition called pelvic inflammatory disease, or PID. That can be a painful condition where there's lower abdominal pain, pain during sex, and inflammation of the pelvic organs. If it gets up into the upper genital tract, it can cause scarring in the fallopian tubes, and that scarring can lead to the egg not being able to be fertilized properly or not being able to travel down the fallopian tube.

Another complication that can come from the fallopian tubes being scarred or damaged from a chlamydia infection is called ectopic pregnancy, where the egg can actually get fertilized outside the uterus (for example, in the fallopian tube), and that can be life threatening. In pregnant women who have chlamydia or acquire chlamydia while they're pregnant, chlamydia can be passed to the infant during vaginal childbirth. In a newborn infant, chlamydia can cause eye infections (conjunctivitis) and it can also cause pneumonia, which is why we really encourage all pregnant women to be tested for chlamydia and treated if they're positive.

Usually men don't suffer any long-term consequences of a chlamydia infection. In a very small portion of men, the infection can travel into the upper genital tract and cause an infection of the epididymis [the tube where sperm collect]. And that can cause pain and swelling. That's pretty uncommon, and it can be treated and it doesn't result in infertility in men.

How is chlamydia transmitted from person to person?

Probably the most common mode of transmission is through vaginal sex--sexual intercourse. But it is possible to get it from anal sex and oral sex.

What factors might put a person at risk for chlamydia?

The most important thing is having sex without using a condom. The more sex partners you have, the more likely it is that you're going to come into contact with chlamydia. And what we call concurrent partnerships, where you're having sex with someone who's also having sex with other people. Having sex with more than one person at a time increases the odds that the infection can be passed between people.

What are the symptoms of chlamydia?

Most chlamydia infections in both men and women have no symptoms. When symptoms do occur, in men there can be burning with urination or a discharge from the penis, or burning or pain around the urethra--the opening to the penis. In women, symptoms can include vaginal discharge, and perhaps some slight bleeding or spotting after sex. But often these are nonspecific symptoms that may occur from a variety of infections.

Do I need to get tested for chlamydia?

We recommend that all sexually active women aged 25 and under get tested every year for chlamydia, whether or not they have symptoms. We also recommend chlamydia screening for women over 25 who are at increased risk for chlamydia -- for example, if they have a new sex partner or multiple sex partners. The main reason for this is that women are the ones who have the worst consequences of a chlamydia infection. Women benefit the most from getting tested and treated because we can prevent these long-term complications.

We don't recommend routine screening for men. In men, any long-term complications are extremely rare.

What tests are used to diagnose chlamydia?

There are several ways to test for chlamydia. Usually it's a very easy thing to do. The test can be done using a urine sample or it can be done during a routine pelvic exam where the clinician collects a swab either from the cervix or from the vagina. Patients can collect the specimen themselves with something called a vaginal swab. Usually the results take a few days to a week to come back.

A chlamydia test isn't automatically done at the time that a Pap test is done. Many physicians will do it at the same time, but it's important for women to ask their doctor – sexually active women aged 25 and under should make sure that they're getting a chlamydia test every year and not just assume it's being done when they have their annual pelvic exam or Pap test.

How is chlamydia treated?

If someone has a chlamydia infection, it's really important that not only they get treated, but that they make sure their partners get treated too. The treatment for chlamydia is very safe and effective and easy. A single dose of azithromycin or a one-week course of doxycycline can be used.

It is possible to get chlamydia again. In fact, the re-infection rates are really high. So we also recommend that…any time someone has a chlamydia infection, they should come back three months later and get another test to make sure they don't have a repeat infection.

What are the best ways to avoid getting chlamydia?

The best way to prevent getting chlamydia is either to not have sex, or for people who are having sex, to use a condom every time and to use it correctly every time. Also to minimize the number of partners that they have sex with and to minimize the number of partners who have other partners at the same time.