Table 5. HIV-Related Laboratory Monitoring Schedule During Pregnancy

√^b

√

If a result is not available within 2 weeks of ART initiation or modification

√

√

Until HIV RNA levels are undetectable

√

At least every 3 months^d

√

√ ^b

√

Patients who have been on ART for <2 years and have CD4 counts of <300 cells/mm³, those with inconsistent adherence, or those with detectable viral loads should have CD4 counts monitored every 3 months during pregnancy.^e

√

√

If abacavir use is anticipated

√

√

√

With additional testing as clinically indicated

√

√

√

With additional testing as clinically indicated

^a For additional information, see Laboratory Testing in the Adult and Adolescent Antiretroviral Guidelines.

^b Prior HIV-related illnesses and past plasma HIV RNA levels and CD4 counts should be reviewed at entry into antenatal care.

^c The plasma HIV RNA levels of pregnancies impacted by HIV should be monitored at the initial antenatal visit with a review of prior HIV RNA levels (AI), 2 to 4 weeks after initiating (or changing) ART (BI), monthly until RNA levels are undetectable (BIII), and then at least every 3 months during pregnancy (BIII). Obtain an HIV RNA level at the time of ART initiation or modification if a recent result within 2 weeks prior is not available. 

^d More frequent viral load monitoring (every 1–2 months) may be indicated for patients who are taking ARVs that have been shown to have reduced drug levels in the second and third trimesters (e.g., cobicistat, elvitegravir, rilpivirine) and are potentially at risk for loss of viral suppression (see Table 6, Table 7, and Antiretroviral Therapy Use During Prepregnancy and Early Pregnancy).

^e CD4 count should be measured at the initial antenatal visit (AI). Patients who have been on ART for ≥2 years and who have had consistent viral suppression and CD4 counts that are consistently >300 cells/mm3 do not need to have their CD4 counts monitored after the initial antenatal visit during this pregnancy, per the Adult and Adolescent Antiretroviral Guidelines (CIII). Patients who have been on ART for <2 years and have CD4 counts of <300 cells/mm3, those with inconsistent adherence, or those with detectable viral loads should have CD4 counts monitored every 3 months during pregnancy (CIII). Those on ART<2 years and with CD4 counts >300 cells/mm3 should have CD4 monitored every 6 months.

^f ARV drug-resistance testing (genotypic testing and, if indicated, phenotypic testing) should be performed in patients whose HIV RNA levels are above the threshold for standard resistance testing (usually >500 copies/mL to 1,000 copies/mL but may be possible for HIV RNA >200 to ≤500 copies in some laboratories). Testing should be performed before—

• Initiating ART in pregnancy when ARV drugs were never taken previously and testing for ARV drug resistance was not previously conducted (AII);
• Initiating ART in pregnancy when ARV drugs were previously being taken (AIII); or
• Modifying ARV regimens for pregnancy that occurs while receiving ARV drugs or for suboptimal virologic response to ARV drugs that were started during pregnancy (AII).

ART should be initiated in pregnancy prior to receiving the results of ARV-resistance tests. ART should be modified, if necessary, based on the results of the resistance tests (BIII).

^g Patients who are taking ART during pregnancy should undergo standard gestational diabetes screening (AIII). 

^h Laboratory testing to monitor complications of ARV drugs during pregnancy should be based on what is known about the adverse effects of the drugs being taken (e.g., hematologic monitoring for those receiving ART regimens containing zidovudine, serum creatinine monitoring for those receiving ART regimens containing tenofovir) (AIII).

Key: ART = antiretroviral therapy; ARV = antiretroviral; CD4 = CD4 T lymphocyte