T-shaped IUD with copper surface reduced pregnancy rate.
D003267:Contraception; D005069:Evaluation Studies as Topic; D005193:Family Planning Services; D007434:Intrauterine Devices; D012106:Research
Contraception; Contraceptive Effectiveness; Contraceptive Methods--pharmacodynamics; Evaluation; Family Planning; Iud--pharmacodynamics; Size; Summary Report; Use-effectiveness