Chlamydia is a common sexually transmitted infection (STI) caused by the bacterium Chlamydia trachomatis. Many infected people do not experience noticeable symptoms, allowing the infection to persist untreated. When present during pregnancy, the infection can lead to adverse outcomes for both the pregnant individual and the newborn. This article details the risks, complications, and standard medical protocols for screening and management.
Chlamydia’s Link to Fetal Death
While Chlamydia is a serious infection in pregnancy, it is not considered a primary or common cause of stillbirth, defined as fetal death occurring after 20 weeks of gestation. Some studies suggest a history of Chlamydia infection may be associated with an increased risk for stillbirth, but a direct cause-and-effect relationship is not established.
Stillbirth, when associated with Chlamydia, is often an outcome of severe, untreated maternal infection leading to systemic complications. The infection can trigger inflammation within the reproductive tract, which may lead to the premature rupture of membranes or extreme preterm birth. Fetal death in these cases is related to complications of prematurity or a severe intrauterine inflammatory response, rather than direct fetal toxicity by the bacterium itself. Prompt screening and treatment significantly mitigate this potential risk.
Other Pregnancy and Neonatal Complications
The primary risks associated with untreated Chlamydia during pregnancy relate to morbidity, affecting the timing of birth and the health of the newborn. Spontaneous preterm birth is a significant risk, where the infection triggers inflammation that can lead to early contractions or the premature rupture of membranes. Untreated infection is also associated with intrauterine growth restriction, resulting in the baby being small for their gestational age and having a low birth weight.
Transmission of the bacteria to the baby occurs as the newborn passes through the infected birth canal during a vaginal delivery. The newborn can contract C. trachomatis, leading to two specific infections. Neonatal conjunctivitis (ophthalmia neonatorum) causes eye redness, swelling, and discharge, appearing within the first few weeks after birth. Exposed infants can also develop Chlamydial pneumonia, a distinct lung infection that develops between four and twelve weeks after birth.
Screening Guidelines for Pregnant Individuals
Routine screening for Chlamydia is recommended for all pregnant individuals at the initial prenatal visit, within the first trimester. This is done regardless of perceived risk factors because the infection is frequently asymptomatic.
The preferred method of diagnosis is a nucleic acid amplification test (NAAT), performed on a urine sample or a swab taken from the cervix or vagina. Individuals who are 25 years of age or younger, or those who have continued risk factors like a new sex partner or multiple partners during pregnancy, should receive re-screening. This repeat screening is recommended during the third trimester to ensure the mother is infection-free at the time of delivery.
Treatment and Management During Pregnancy
Immediate and effective treatment is paramount upon diagnosis to prevent adverse pregnancy and neonatal outcomes. The antibiotic regimens used are safe for the developing fetus while effectively clearing the bacterial infection. Azithromycin, taken as a single 1-gram oral dose, is the first-line treatment due to its high efficacy and convenience.
Amoxicillin, taken as a 500-milligram dose three times daily for seven days, is a common alternative if Azithromycin cannot be tolerated. Doxycycline is avoided because it can interfere with fetal bone and tooth development. A “test of cure” (TOC) is mandated for pregnant individuals, performed three to four weeks after completing the antibiotic course, to confirm the infection has been eradicated. The pregnant individual’s sexual partner must also receive treatment to prevent re-infection.