PRELIMINARY REPORT ON THE MEDICAL FOLLOW-UP STUDY OF THE NEW INTRA-UTERINE CONTRACEPTIVE DEVICES.
D002681:China; D003273:Contraceptive Devices; D005193:Family Planning Services; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007434:Intrauterine Devices; D011247:Pregnancy; D013223:Statistics as Topic
CHINA; FAMILY PLANNING; PREGNANCY; STATISTICS