Chlamydia is one of the most commonly reported sexually transmitted infections (STIs), often presenting without noticeable symptoms. Standard pregnancy tests, whether performed at home with urine or in a clinic with blood, function by detecting Human Chorionic Gonadotropin (hCG). This hormone is produced by the developing placenta shortly after a fertilized egg implants in the uterine wall. Understanding how this bacterial infection interacts with pregnancy detection is a common concern.
How Chlamydia Interacts with Pregnancy Test Accuracy
The primary concern about Chlamydia affecting a pregnancy test is whether the infection could interfere with the test’s ability to read the hCG hormone. However, Chlamydia does not directly interfere with the biochemical accuracy of a standard pregnancy test. The test is specifically designed to identify the beta subunit of hCG, a unique glycoprotein hormone produced only during pregnancy.
The bacterium primarily targets cells in the reproductive tract. Because Chlamydia does not produce hCG, nor does it interact with the antibodies used by the test strip, it cannot cause a false positive result. The presence of the infection also does not suppress the body’s production of hCG, meaning it will not cause a false negative result.
The infection may indirectly influence the outcome of a pregnancy, which could then affect hormone levels. Untreated Chlamydia can increase the risk of an ectopic pregnancy, where a fertilized egg implants outside the uterus. Ectopic pregnancies can result in lower-than-expected hCG levels, potentially leading to a negative test result if the test is taken very early. The infection itself does not chemically confuse the test.
Potential Health Complications for Mother and Child
Having an active, untreated infection during pregnancy poses significant risks to both the mother and the developing fetus. For the mother, untreated Chlamydia increases the likelihood of premature rupture of membranes, which can lead to preterm labor and delivery (birth before 37 weeks of gestation).
Untreated maternal infection is also associated with an increased risk of postpartum endometritis, an infection of the uterine lining after delivery. For the baby, the primary risk occurs during a vaginal delivery, where the infant is exposed to the bacteria. This exposure can lead to serious eye infections, known as neonatal conjunctivitis, which develops within the first month of life.
Furthermore, transmission during birth can result in the infant developing Chlamydia pneumonia, a potentially serious lung infection. Without treatment, the rate of transmission from mother to baby can be as high as 50 to 70%. The infection is also linked to other adverse pregnancy outcomes, including low birth weight and fetal loss.
Essential Next Steps for Testing and Care
Regardless of the pregnancy test result, anyone concerned about a Chlamydia infection should seek immediate testing and consultation with a healthcare provider. Chlamydia is easily diagnosed using a urine sample or a swab of the affected area. Early detection and treatment are essential for preventing the serious complications associated with the infection during pregnancy.
The infection is curable with antibiotics, and treatment is safe for the developing fetus. First-line therapy involves a single dose of the antibiotic azithromycin. A test-of-cure is recommended approximately four weeks after treatment to ensure the infection is fully eradicated. Prompt treatment protects the mother’s health and significantly reduces the risk of transmitting the bacteria to the newborn during delivery.