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Abstract
Gallstones remain one of the most common medical problems leading to surgical intervention. Every year, approximately 500.000 cholecystectomies are performed in the US. It has been well demonstrated that the presence of gallstones increases with age. During the reproductive years, the female-to-male ratio is about 4:1, with the sex discrepancy narrowing in the older population to near equality. The risk factors predisposing to gallstone formation include obesity, diabetes mellitus, estrogen and pregnancy, hemolytic diseases, and cirrhosis (Schirmer et al., 2005).
Cholelithiasis is the most common form of benign gallbladder disease that results in major health expenditure. Female sex hormanes are causally related to cholesterol gallstone disease, which are more common in woman than in men. The risk of choletithiasis is further enhanced by the use of exogenous female sex hormones and by pregnancy (Dhiman and Chawia, 2006).
Individual who take contraceptive steroids or estrogen are at increased risk of developing cholesterol gallstones. The mechanisms of the increased stone formation are incompletely understood.
The factores responsible include an increase in cholestrerol saturation of bile and an increase in rate of secreation of cholesterol into bile. It was found that cholesterol absorption, cholesterol synthesis, chylomicron remnant clearance and the concentration of plasma and lipoproten lipids were not altered by contraceptive steiods (Kern, et al., 1990).