A Baby Developed Chlamydia in Eye—How Does That Happen?

Generally, many people regard chlamydia as a sexually transmitted infection (STI) that affects the reproductive organs. Chlamydia causes discharge and pain during urination or sex, for example—above all else. 

But a photo published in 2019 in the New England Journal of Medicine (NEJM) shows that the infection can also occur in a much more visible place: the eyes.

The photo was taken when a couple brought their two-week-old baby girl to an ophthalmology clinic in Malaysia. The parents had noticed pus-like discharge—a symptom of conjunctivitis (pink eye)—from the baby's eyes for the previous three days.

The healthcare providers took a sample of that discharge, and the results came back positive for chlamydia. How can that happen? Well, here's what you should know about chlamydia infections, including how the bacteria can infect newborns during childbirth.

A Quick Overview of Chlamydia

Before we unpack exactly how chlamydia infects the eyes, here's a quick refresher: Chlamydia is almost always an STI caused by the bacteria Chlamydia trachomatis.

Also, chlamydia is one of the most common STIs in the United States. In 2020, the Centers for Disease Control and Prevention (CDC) reported more than 1.5 million cases of chlamydia in the United States.

Chlamydia most commonly affects the cervix in women and the urethra in men. Although it may not cause any symptoms initially, chlamydia can eventually cause the following:

• Inflammation
• Pain
• Baginal or penile discharge
• A burning sensation during sex or urination. 

In women, chlamydia can also cause pelvic inflammatory disease. The STI can also lead to pregnancy and childbirth problems.

How Is Chlamydia Transmitted

You can get chlamydia by having vaginal, anal, or oral sex with an infected person. Besides the cervix or urethra, chlamydia can infect the rectum through anal sex or the throat through oral sex. 

Additionally, a pregnant person with chlamydia can transmit the bacteria to the fetus during childbirth, which was the case in the scenario outlined in the NEJM.

How Chlamydia Can Get into the Eyes

The baby's mother also tested positive for chlamydia—in her cervix, not in her eyes. Healthcare providers concluded that the baby's eyes became infected during childbirth, resulting in ophthalmia neonatorum.

Ophthalmia neonatorum is a type of pink eye caused by either chlamydia or gonorrhea. Pink eye causes the clear membrane protecting the eye's outer layer to become infected or inflamed. In the NEJM article, the authors noted that in pregnant people, a routine prenatal screening could detect ophthalmia neonatorum.

Traveling through an infected birth canal isn't the only way a person can develop chlamydia in their eye. It's also possible that bodily fluids infected with Chlamydia trachomatis can get into a person's eye during sexual activity, resulting in similar symptoms.

Treating Chlamydia

Chlamydia is treatable. Per the NEJM article, healthcare providers prescribed antibiotics to the baby and the parents. The baby's symptoms went away within five days. Two weeks later, the healthcare providers reported that the baby remained healthy and clear-eyed.

Of course, it's always better to prevent disease transmission first rather than treat it after symptoms already set in. During sexual activity, using condoms can help limit the spread of chlamydia. 

But if you're trying to get pregnant, ensure you and your partner have tested for STIs. Regular testing can protect you—and any children in your future—from getting chlamydia.

A Quick Review

Chlamydia is a common STI that most often affects the cervix and urethra in women and men. However, chlamydia can also be spread during the birthing process as the fetus travels through the birth canal.

Antibiotics can clear up chlamydia, so seeing a healthcare provider if you have a chlamydia infection is important.