A successful pregnancy is characterised by an increase in Th2
cytokines and suppression of Th1
cytokine production. A Th1 to Th2
cytokine shift is also observed in the
disease progression of
HIV infection.
Highly active antiretroviral therapy (
HAART) suppresses HIV
viremia, increases CD4+ cell counts and counteracts the Th1 to Th2 shift. We hypothesised that the increased risk of premature delivery reported in HIV-infected,
HAART-treated pregnant women is mediated through changes in the
cytokine environment in pregnancy. Here, we present results relating to levels of
interleukin (IL)-2 (Th1) and
IL-10 (Th2) in peripheral blood mononuclear cells (PBMCs) measured three times during pregnancy in 49 HIV-infected women. Slope values representing the trend of repeated
cytokine (IL-2-PHA, IL-2-Env, IL-10-PHA and IL-10-Env) measurements within women during pregnancy were estimated and median values compared by prematurity and
HAART use. Multiple regression adjusted for
HAART and
cytokine slope clarified the additional and independent effect of
HAART on prematurity risk. Results showed favourable
immunomodulation induced by
HAART with increased
IL-2 and decreased
IL-10.
HAART use and IL-10-Env slopes were not significantly associated with prematurity risk, but each unit increase in IL-2-PHA slope was associated with an 8% increased risk of premature delivery (AOR, 1.08; 95% CI, 1.0-1.17; p=0.005).
HAART use in pregnancy provides significant benefits in delaying HIV
disease progression and reducing the risk of mother-to-child-transmission, but may be counterproductive in terms of successful pregnancy outcome.