Liver damage from low-dose oral contraceptives

Area of Science:

• Pharmacology
• Hepatology
• Drug Safety

Background:

• Oral contraceptives (OC) have evolved with reduced hormone content.
• Adverse liver reactions have been associated with older, higher-dose formulations.
• Understanding the safety profile of low-dose OC regarding liver health is crucial.

Purpose of the Study:

• To determine if decreased estrogen and gestagen in modern low-dose oral contraceptives (OC) correlate with a lower incidence of adverse liver reactions.
• To characterize the biochemical patterns of liver injury associated with low-dose OC use.

Main Methods:

• A retrospective survey of all OC-related liver adverse events reported to the Swedish Adverse Drug Reactions Advisory Committee (SADRAC) between 1966 and 1989.
• Calculation of the incidence of reported adverse liver reactions based on OC sales (defined daily dose [DDD]).

Main Results:

• A significant decrease in the incidence of reported liver reactions was observed with medium-dose estrogen OC compared to high-dose formulations.
• Low-dose estrogen OC showed a further, though not statistically significant, decrease in reported liver reactions.
• Higher gestagen doses in OC were associated with a trend towards increased reporting rates of liver adverse events.
• Cholestatic and hepatocellular patterns were equally common in low-dose OC users experiencing liver reactions; no liver tumors were reported.

Conclusions:

• The reduction in both estrogen and gestagen content in combined-preparation oral contraceptives (OC) appears to be associated with a decreased incidence of adverse liver reactions.
• Low-dose OC formulations demonstrate an improved liver safety profile compared to older, higher-dose versions.