Coronary thrombosis, cerebrovascular accidents and venous thrombosis are more likely to occur in women aged 35 years or over, particularly if they have used the contraceptive for longer than five years, if they smoke, if they are obese or if they are hypertensive. Additional risk factors are diabetes, hypercholesterolaemia and familial hyperlipoproteinaemia. However, the risk of mortality due to oral contraceptives in women under 35 who are in the high-risk group is in general far less than the risk of mortality due to pregnancy. It is usually mild and reversible, but regular blood pressure checks including a pre-treatment level are advisable. Prolonged amenorrhoea following the use of oral contraceptives may occur.
Caution is advised where oligomenorrhoea or amenorrhoea have occurred in the past.
Mood changes, weight gain, skin pigmentation, vaginal candidiasis, gall bladder disease, gastro-intestinal irritation and fluid retention may occur. Case reports have been published of benign hepatic tumours in women on oral contraceptives for a prolonged time, but a causal relationship has not been established. The preparation should be discontinued if sudden upper abdominal pain develops. With vomiting or diarrhoea, the absorption of oral contraceptives may be diminished and women should be advised to use additional methods of contraception at the time of such disorders. The efficacy of Brevinor may be decreased by the concomitant administration of aminopenicillins.