Apr 26, - Birth control pills may cause breast enlargement or tenderness. the nature of the discharge, and changes which can affect sexual g: yaz | Must include: yaz. Jul 9, - Yaz is an oral contraceptive (combination birth control pill) that received U.S. . what is known as menstruation (a period), or the regular discharge of blood and . menstrual periods, nausea, breast tenderness and headache.