Hematological effects of zidovudine prophylaxis in newborn infants with and without prenatal exposure to zidovudine

Postnatal prophylaxis with oral zidovudine (ZDV) is associated with hematological effects. However, it is still unknown whether selection of non-ZDV-based regimens in pregnancy may reduce hematological toxicity associated with postnatal ZDV prophylaxis. The aim of this study was to define the hematological effects of ZDV prophylaxis in newborns with and without prenatal exposure to ZDV. Sixty-five newborns from mothers infected with HIV who, during pregnancy, received HAART regimens with (n:44) and without (n:21) ZDV were evaluated. Virological and hematological data were compared at birth and at 4 weeks and 6 months of life. Newborns with prenatal ZDV exposure had significantly worse hematological values at birth, with lower levels of hemoglobin (14.3 g/dl vs. 16.2 g/dl, P=0.001), red blood cell count (3.45 × 10(6) cells/mm(3) vs. 4.48 × 10(6) cells/mm(3), P<0.001), and hematocrit (41.0% vs. 46.8%, P<0.001), and higher values of mean corpuscular volume (119 fl vs. 103 fl, P