Relationship between Asymtomatic Brucella Infection and Spontaneous Abortion

Brucella infection in animals has got documented association with high incidence of abortion, but in human there are controversies about the role of brucellosis in spontaneous abortion. Since brucellosis is endemic in Iran and is a disease that can be diagnosed and treated and many causes of abortion are undiagnosed, this study was designed to evaluate probable association between maternal brucella infection and spontaneous abortion. This clinical-trial study was done in the year 2006 at Amir-al Momenin Hospital of Semnan University of Medical Sciences. 81 women with spontaneous abortion were considered as case and 103 women with normal pregnancy outcome as control group. Previous pregnancy rates, previous abortion rates, and pregnancy age were similar in both groups. Two milliliter blood samples obtained from each one and IgG and IgM antibody measured by ELISA method in both groups. IgG or IgM equal or greater than ten considered positive. Individual, pregnancy age, fresh cheese and milk consumption, blood examination tests were gathered in a questionnaire and analyzed by descriptive statistics and statistical tests with significance of 5%. Both groups were matched based on age, number of previous pregnancies and abortion, pregnancy age and consumption of fresh cheese. 6.2% of cases and 13.6% of control group had positive IgG titer (IgG≥ 10 units). In both groups IgM was negative (IgM<10 units). There was no significant relationship between brucella antibody and spontaneous abortion. There was significant relationship between raw milk consumption and spontaneous abortion (OR=6.31). This study showed that asymptomatic brucella infection has no role in spontaneous abortion.