CD4 and CD8 counts are widely used prognostic markers to assess the degree of immune impairment in HIV seropositive individuals and to monitor anti-retroviral therapy (ART). Pregnancy is considered as a physiologically immunocompromised state, hence alterations in T lymphocyte subsets may occur during pregnancy. There is a need to establish base-line values of these counts, especially in healthy pregnant women. One hundred healthy HIV seronegative pregnant women (mean age 22.5 +/- 2.99 yr) in their third trimester of pregnancy and 30 non-pregnant women (mean age 22.7 +/- 3.01 yr) were tested for their CD4 and CDS counts. In pregnant women, the CD4 and CD8 cell counts/microl were 764 +/- 249 and 547 +/- 196 and the CD4 and CD8 per cent were 56.49 +/- 8.3 and 38.03 +/- 7.2 respectively. In the non-pregnant women CD4 and CD8 counts/microl were 965 +/- 267 and 639 +/- 211 whereas the CD4 and CD8 per cent were 55.27 +/- 5.99 and 36.17 +/- 6.44 respectively. Absolute counts were significantly lower (P < 0.05) in the pregnant group as compared to the controls. A wide variation was seen in the CD4 and CD8 counts in both the groups. However, the variations in the mean CD4 and CD8 per cent were much smaller. Thus CD4 and CD8 per cent may be considered as a useful indicator of immune function rather than absolute counts, in pregnant women.