Liver damage from low-dose oral contraceptives.

Abstract

OBJECTIVE: To study whether the decrease in the content of oestrogen and gestagen in modern low-dose oral contraceptives (OC) has yielded a lower incidence of adverse liver reactions, and to describe the biochemical pattern of the adverse liver reactions from low-dose OC. DESIGN: We surveyed all liver reactions from OC reported to SADRAC (Swedish Adverse Drug Reactions Advisory Committee) from 1966 to 1989. MAIN OUTCOME MEASURE: Incidence of reported adverse liver reactions (number of reported adverse reactions/OC sales in defined daily dose [DDD]). RESULTS: There was a sharp decline in the number of reports during the studied period, suggesting changes in reporting habits. However, there was also a significantly lower incidence of reports for medium-compared to high-oestrogen dose OC, and a further decrease, albeit non-significant, in incidence with low-oestrogen dose OC. Furthermore, in three comparisons of pairs of OC that differed only in the gestagen dose, there was a strong trend towards a higher reporting rate with higher gestagen dose. Cholestatic and hepatocellular liver enzyme patterns were equally frequent in patients with adverse reactions from low-dose oestrogen OC. There was no report of liver tumours related to use of low-oestrogen dose OC. CONCLUSION: There seems to be a decrease in the incidence of adverse liver reactions related to lower contents of both oestrogen and gestagens in OC of the combined-preparation type.