This study was undertaken in order to evaluate the effect of brucellosis in pregnancy. The serum agglutination test, Coombs and/or blood culture systems were used in the diagnosis of brucellosis. From July 2003 to September 2010, the clinical and delivery patterns of 40 healthy pregnant women were compared with 39 pregnant women who had brucellosis. There were no birth defects, anomalies or mortalities. We observed that brucellosis in pregnancy increases the incidence of preterm delivery (P = 0.01) and low birth weight (P = 0.001) from that seen in general deliveries. A cephtriaxone/rifampicin combination was found to be the most effective treatment in pregnant women infected with brucellosis (P = 0.004). Brucellosis in pregnancy has no effect on the incidence of congenital malformations or stillbirths. Preterm delivery and low birth weight can be seen as pregnancy outcomes in brucellosis. Appropriate antimicrobial therapy of brucellosis in pregnancy will reduce morbidity and prevent complications.