Major studies on population authorized by United States Congress.
D000569:Americas; D003267:Contraception; D019049:Developed Countries; D004467:Economics; D005069:Evaluation Studies as Topic; D005193:Family Planning Services; D009656:North America; D011640:Public Policy; D013672:Technology; D014481:United States
Americas; Contraception; Developed Countries; Economic Factors; Evaluation; Family Planning; North America; Northern America; Policy; Population Policy; Social Policy; Technology; United States