Antiretroviral (ARV) drug detection in meconium following any 3rd trimester or only 2nd trimester maternal ARV prescription. Numbers above bars indicate total meconium specimens with 3rd or 2nd trimester exposure. 2nd trimester drug detection only occurred in some samples with LPV, EFV, and TFV exposure. Zidovudine (AZT) meconium drug detection data not shown (see text). No amprenavir exposure cases were included in this population. RTV, ritonavir; LPV, lopinavir, ATV, atazanavir; DRV, darunavir; NFV, nelfinavir; SQV, saquinavir; NVP, nevirapine; EFV, efavirenz; RAL, raltegravir; 3TC, lamivudine; TFV, tenofovir; FTC, emtricitabine; ABC, abacavir; d4T, stavudine.