Chlamydia Infection in Pregnancy

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Sexually transmitted diseases (STDs) can be uncomfortable and inconvenient. However, many have no symptoms at all. Nevertheless, even the asymptomatic ones can have devastating consequences. And when you’re pregnant, many STDs can affect your baby, and not in a good way. In this blog we’re going to look at one of the common ones known as chlamydia.

Chlamydia Basics

Chlamydia is due to a variety of bacteria known as Chlamydia trachomatis. The germ was discovered in 1907 and found to be responsible for a potentially serious eye disease known as trachoma. This has been found primarily in developing countries. In developed countries, however, the infection is responsible for a variety of other conditions—and it’s quite common. In fact, it’s so common that it’s estimated that around 3 million cases occur in the United States each year.

Who gets chlamydia? Anyone who is sexually active is at risk; outside of infancy, it’s almost exclusively transmitted through sexual contact. Since the germ can live in the mouth, penis, vagina or anus, males and females can both carry chlamydia. However, it’s more prevalent in teens and young adults. This is partly because it’s at this age that people are most likely to have sex with a variety of partners. Also, the vaginal lining of younger women is different than that of older women and is more compatible with chlamydia infection.

You might be wondering what symptoms to look for that might be caused by chlamydia. Problem is, there may be none: most cases have no symptoms. Those that are symptomatic may have a discharge down below or pain in urination; the discharge is more common in females than males. Those with an anal infection may have some rectal itching or pain. Although oral (mouth) infections occur, most have no symptoms.

Chlamydia, Fertility, and Pregnancy

Among the complications we typically see as a result of chlamydial infection, probably the most feared are those that are related to a woman’s reproductive system. The chlamydia germ may enter a woman’s body through the vagina and also readily infects the cervix. From there, however, some move up the cervix to the uterus and the Fallopian tubes—essentially the reverse path that a baby takes during conception and delivery. In these locations, it can cause a more severe infection which leads to pelvic inflammatory disease (PID).

Not only can PID cause pain in the pelvic area. It can damage the uterus and Fallopian tubes and lead to problems with fertility. Women with PID complications who do become pregnant may have what’s known as an ectopic pregnancy. That’s a pregnancy in the wrong place, usually the Fallopian tube, and can be life-threatening to the woman.

Infected women without PID may go on to have a normal pregnancy, but the problems don’t end there. Babies who inherit chlamydia at birth can develop a significant conjunctivitis (“pinkeye”). Pneumonia is also a risk for our youngest infected patients.

What Providers Do (and….What Patients Should Get Done)

Chlamydia screening has gotten easier and more accurate over the years, and there are now some choices as to how to do it. The test can still be done by a vaginal swab in women (and a swab of the urethra, just inside the tip of the penis, in men). A rectal swab can be done if there is a chance that that area has been exposed. However, labs can now do the test from a urine sample; the accuracy is comparable to that of the swabs.

Because of the ease of testing, the complications of untreated chlamydia, and the fact that it’s pretty common, it’s recommended that sexually active young women get the test annually—more frequently if there’s a change of partner. Pregnant women should get the test at least once; many providers would do a second test later on in younger women or those at higher risk (such as those with a change of partner).

Fortunately, for those who test positive for chlamydia, there are good treatments. As so often happens in pregnancy, there are fewer choices for medications. However, one that’s OK happens to be the easiest to take—a single dose of azithromycin. Azithromycin-allergic pregnant women should work with their provider for an alternative; sometimes amoxicillin is used in pregnancy.

It’s important that any sexual partners be treated. Where treatment is concerned, situations vary, as do providers and state health departments. This is another great time for a dialog with your provider as to how to handle treatment of any partners. Since anyone can get chlamydia again, it’s also recommended that infected individuals be tested three months after taking the medication.

It’s unfortunate that chlamydia continues to threaten the health of women and their young infants. The good news is that testing is easier, treatment appears to be safer, and women treated in good time can go on to have healthy pregnancies and healthy newborns.

Stan Sack
Dr. Stan Sack has 29 years’ experience as a primary care pediatrician in Massachusetts and Florida. A medical writer since 2015, he enjoys blogging on topics that are on parents’ minds but are covered less often in books and on websites. He lives in the Florida Keys with his family and enjoys healthy cooking, fitness activities and singing in his spare time.

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