Peptic ulceration and the use of oral contraceptives.  A negative correlation attributable to the disease?
D000328:Adult; D003075:Coitus; D003267:Contraception; D003276:Contraceptives, Oral; D005260:Female; D006801:Humans; D007247:Infertility, Female; D010437:Peptic Ulcer; D013223:Statistics as Topic
D003276:Contraceptives, Oral