To evaluate the longitudinal growth patterns of infants born to HIV-infected and uninfected mothers in Malawi, Africa, 92 HIV-infected infants, 270 uninfected infants born to HIV-infected mothers, and 686 infants born to uninfected mothers between birth and 24 months of life were studied. Weight and length were evaluated longitudinally utilizing generalized estimating equations. HIV-infected children were compared with uninfected children born to HIV-infected and uninfected mothers, and to United States National Center for Health Statistics (NCHS) growth standards. Median weight and length-for-age of seronegative infants born to either seronegative or seropositive mothers approximated the NCHS median from birth to approximately 4 months of age. Median weight and length of HIV-infected infants deviated from the NCHS median at an earlier age, and the deviation was more pronounced than was observed for uninfected infants. Mean growth curves constructed by generalized estimating equations indicated that HIV-infected and uninfected infants born to HIV-infected mothers weighed less and were smaller than infants born to HIV-uninfected mothers initially. Mean weight and length of uninfected infants attained the median of infants born to uninfected mothers by 24 months of age, while HIV-infected infants remained below this median. The difference in mean weight-for-age for HIV-infected and uninfected infants born to HIV-infected mothers was statistically significant from birth. The difference in mean length-for-age was statistically significant after 5 months of age. Thus, although infants born to HIV-infected mothers were smaller and weighed less initially, uninfected infants caught up, while HIV-infected infants remained below the median, and the deficit in weight occurred earlier in life than the deficit in length.