IUD most effective post-coital contraception.
D000569:Americas; D003267:Contraception; D003281:Contraceptives, Postcoital; D003710:Demography; D019049:Developed Countries; D005193:Family Planning Services; D007434:Intrauterine Devices; D007435:Intrauterine Devices, Copper; D009656:North America; D011153:Population; D011157:Population Dynamics; D013997:Time Factors; D014481:United States
D003281:Contraceptives, Postcoital
Americas; Contraception; Contraceptive Methods; Demographic Factors; Developed Countries; Family Planning; Fertility Control, Postcoital; Iud; Iud, Copper Releasing; North America; Northern America; Population; Population Dynamics; Time Factors; United States