WHO provider brief on hormonal contraception and liver disease.

Liver disease, particularly viral hepatitis, is increasingly common. The most frequent causes of long-term, or chronic, viral hepatitis are persistent infections with the hepatitis B or hepatitis C virus. Worldwide, 400 million people are chronic carriers of the hepatitis B virus [1]. Each year, between 500,000 to 1.2 million people die from progression of this viral infection, making it the 10th leading cause of death worldwide [1]. An effective vaccine against the hepatitis B virus is available. As vaccine programs are implemented more widely, the global burden of disease caused by the hepatitis B virus should decrease. Currently, infection with the hepatitis C virus is less common than with the hepatitis B virus. Because there is no effective vaccine against the hepatitis C virus, infection with the hepatitis C virus may become more common than infection with the hepatitis B virus in the future. Of the 4 million people newly infected with the hepatitis C virus each year, approximately 70% go on to develop the long-term disease of chronic hepatitis [2]. Chronic hepatitis over a long period of time damages liver cells which may lead to irreversible scarring, which is called cirrhosis. Besides chronic infection, cirrhosis of the liver may also be caused by toxins, such as alcohol, or by genetic, vascular or biliary disorders.