Snapshot A 23-year-old woman presents to clinic with a positive pregnancy test. Two weeks ago, after having a fever and rash, she tested positive for HIV at the local health department. She is hoping to become a parent and wishes to maintain the pregnancy. In addition to typical prenatal counseling and testing, she has labs drawn for CD4 cell counts and plasma HIV RNA. She is initiated on antiretroviral therapy. Introduction Overview proper treatment of HIV during pregnancy, labor, and delivery can reduce maternal complications reduce risk of perinatal transmission Epidemiology incidence < 5,000 estimated cases of HIV in pregnancy annually in the U.S. risk factors for HIV sex with an infected person multiple sex partners unprotected sex first sexual intercourse at a young age history of sexually transmitted infections (STI) injection substance use risk factors for perinatal transmission vaginal delivery in patients with high viral load Pathogenesis perinatal transmission exposure to blood and vaginal secretions during delivery transplacental circulation during uterine contractions Prognosis with proper treatment and low or undetectable viral loads (≤ 1,000 copies/mL) perinatal transmission <1% Presentation History +/- opportunistic infections, tuberculosis, and other STIs Symptoms new HIV infection fever dyspnea weight loss may be asymptomatic advanced HIV infection thrush cachexia co-occuring STIs genital ulcers vaginal discharge Imaging Ultrasound indications at initial visit for gestational age important as early delivery may reduce transmission Studies Serum labs CD4 cell counts at initial visit and every 3 months every 6 months for patients with long-term viral suppression plasma HIV RNA initial visit at antiretroviral initiation 2-4 weeks after antiretroviral initiation/changes monthly until viral load suppressed every 3 months after viral load suppressed at 34-36 weeks to determine delivery timing/mode CBC, BUN, and Cr assess toxicities associated with antiretroviral therapy prior to antiretroviral initiation 3-6 months after initiation Treatment Lifestyle some behavior modifications are associated with reduced risk of perinatal transmission cigarette smoking cessation cessation of recreational substances barrier protection during intercourse with multiple partners Medical antiretroviral therapy (ART) regimen intrapartum IV zidovudine indications HIV RNA > 1,000 copies/mL Surgical cesarean delivery at 38 weeks indications viral load >1,000 copies/mL near term Delivery standard vaginal indications viral load ≤ 1000 copies/mL and on ART Complications perinatal transmission incidence 1-2% with appropriate treatment ~25% without treatment risk factors lack of prenatal care lack of ART treatment breastfeeding smoking substance use mode of delivery treatment ART for infant