Prenatal care ensures the health of both the pregnant person and the developing fetus. A foundational component of this care is the routine screening for sexually transmitted infections (STIs). This screening is a standard part of the patient’s initial prenatal visit, reflecting a proactive strategy to identify and manage potential risks. Healthcare providers incorporate this screening to optimize pregnancy outcomes and confirm that testing is a normal, protective measure.
Standard STI Screening During Pregnancy
Routine STI screening is universally recommended for all pregnant individuals during the first trimester, regardless of perceived risk factors. This initial panel focuses on infections that pose severe risks to the fetus and where early treatment can significantly improve outcomes. Mandatory tests typically include Human Immunodeficiency Virus (HIV), Syphilis, and Hepatitis B (HBV) screening. Testing is administered via a blood draw, often performed alongside other routine first-trimester bloodwork. Screening for Syphilis is important because cases of congenital syphilis have been rising. HIV testing utilizes an “opt-out” approach. Individuals at a higher risk of acquiring an infection during pregnancy are often re-screened for HIV and Syphilis later in the third trimester, typically around 28 to 32 weeks of gestation.
Targeted Testing Based on Risk
While some STI screenings are universal, others are performed on a targeted basis, depending on specific patient factors, history, or local disease prevalence. Chlamydia and Gonorrhea, which can cause complications during pregnancy and delivery, are targeted screenings. These tests are routinely recommended for pregnant individuals under the age of 25, as this demographic has a higher prevalence of these infections. Individuals over 25 years old are screened for Chlamydia and Gonorrhea if they have specific risk factors, such as multiple or new sex partners during the pregnancy, a partner with a known STI, or a history of previous STIs. Hepatitis C (HCV) testing is also recommended based on risk factors, including a history of injection drug use or receiving blood products before 1992. Testing for Chlamydia and Gonorrhea often involves a vaginal swab, which the patient can sometimes self-collect for comfort.
Why Early Detection Matters for Infant Health
Untreated maternal STIs can have severe consequences for the developing fetus and the newborn, justifying rigorous screening protocols. Infections can be passed from the pregnant person to the baby across the placenta during pregnancy, during the birthing process, or sometimes after birth. This vertical transmission can lead to a range of adverse outcomes. Syphilis can cross the placenta and cause congenital syphilis, which is associated with stillbirth, low birth weight, and long-term complications like bone damage, blindness, or neurological damage in the infant. Untreated infections increase the risk of premature labor and low birth weight. Chlamydia and Gonorrhea infections transmitted during delivery can lead to complications in the baby such as eye infections (conjunctivitis) or pneumonia. For viral infections, such as HIV and Hepatitis B, early detection allows for interventions that dramatically reduce the probability of transmission to the baby.
Managing a Positive Diagnosis
Receiving a positive STI diagnosis during pregnancy is managed through well-established treatment protocols. For bacterial infections like Syphilis, the treatment is a course of antibiotics, most commonly Benzathine Penicillin G. This medication is safe in pregnancy and is the only proven treatment for curing the infection in both the pregnant person and the fetus. Chlamydia and Gonorrhea are similarly treated with pregnancy-safe antibiotics, such as azithromycin or ceftriaxone. Viral infections like HIV and Hepatitis B are managed with antiviral therapy. Antiretroviral therapy for HIV is administered during pregnancy to suppress the viral load, which significantly reduces the probability of transmission to the baby. For Hepatitis B, the infant receives a vaccine and Hepatitis B Immune Globulin immediately after birth to prevent infection. Ongoing monitoring and follow-up testing are conducted to ensure the infection has cleared or is properly suppressed.