BOSTON: It is the health issue du jour: has the U.S. been experimenting on humans in its studies of HIV-positive pregnant women in developing countries? The New England Journal of Medicine thinks so — their normally temperate editorial page this week was devoted to a blistering attack on the National Institutes of Health and Centers for Disease Control. The organizations have been giving the AIDS drug AZT to half of the infected mothers in their international study, while the other half get placebos — and according to the journal, this is as ethically shaky as the notorious Tuskegee study, a 1950s experiment that denied syphillis treatment to black men in Alabama. But as TIME Medical Correspondent Christine Gorman reports, the comparison won't wash, "because there is still an open question as to what the effect of AZT in utero is." Not to mention that HIV can also be passed from mother to child by breast-feeding — common enough in the Third World to render AZT treatment futile. While the researchers' ethics may be in question, the CDC is still far away from Tuskegee.