title: A three to four year follow-up study of the intrauterine device in Ceylon.
mesh_terms: D000367:Age Factors; D003276:Contraceptives, Oral; D004521:Educational Measurement; D005260:Female; D005306:Fertilization; D005500:Follow-Up Studies; D006801:Humans; D007434:Intrauterine Devices / Q000009:adverse effects; D009790:Occupations; D010298:Parity; D011247:Pregnancy; D011275:Pregnancy, Unwanted; D013188:Sri Lanka
chemical_list: D003276:Contraceptives, Oral