Since the immediate postpartum period is also associated with an increased risk of thromboembolism, oral contraceptives should be started no earlier than four weeks after delivery in women who elect not to breast feed. In another study in Great Britain, the risk of developing cerebrovascular disease persisted for at least years after discontinuation of oral contraceptives, although excess risk was very small 34. Contact Lenses Contact lens wearers who develop visual changes or changes kabeljau kaufen tricyclen in lens tolerance should be assessed by an ophthalmologist. Tell your doctor about all the prescription and over-the-counter medications you use, including vitamins, minerals and herbal products. Cohort studies provide measure of attributable risk, which is the difference in the incidence of disease between oral contraceptive users and nonusers. Premature Birth Can Lead to Sensory Damage Premature birth can result in lasting sensory damage, the BBC reported Saturday.