Title I: Preventive Health Programs - Preventive Health Amendments of 1984 - Amends the Public Health Service Act to authorize the Secretary of Health and Human Services, acting through the Centers for Disease Control, to make program grants for: (1) lead poisoning prevention; (2) community and school-based fluoridation; and (3) neonatal screening programs for genetic diseases in new-born infants.

Sets forth application requirements.

Requires the Secretary to report to Congress by December 30, 1985, and December 30, 1987, regarding such programs' effectiveness.

Makes Indian tribes eligible for such grants.

Authorizes FY 1985 through 1987 appropriations.

Authorizes FY 1985 through 1987 appropriations for preventive health services: (1) to immunize against vaccine-preventable diseases; and (2) for tuberculosis.

Authorizes the Secretary, acting through the Centers for Disease Control, to make grants for information and education and control of acquired immune deficiency syndrome. Authorizes FY 1985 through 1987 appropriations.

Authorizes FY 1985 through 1987 appropriations for sexually transmitted disease (presently venereal disease) prevention and control projects (research, public information and education, professional training, and State project grants). Increases the appropriation obligations limit from five to ten percent for such non-State project grants. Repeals the existing "venereal disease" definition.

Authorizes FY 1985 through 1987 appropriations for preventive health and health services block grants. Increases minimum population-based State allotments from $3,000 to $3,500.

Bases a State's post FY 1984 hypertension allotments upon 75 percent of its total preventive health services project grant amounts.

Requires States to collect by October 1, 1984, specified preventive health services data.

Repeals the provision prohibiting the Secretary from prescribing specified State block grant certification requirements.

Title II: Title X Programs - Authorizes FY 1985 through 1987 appropriations for family planning services, personnel training, and informational and educational training.

Title III: Title XX Programs - Authorizes FY 1985 through 1987 appropriations for the adolescent family life demonstration program.