Background: Q fever has become a major public health problem in the Netherlands. Infection with Coxiella burnetii (Q fever) during pregnancy has resulted in adverse pregnancy outcome in the majority of reported cases. Therefore, we aimed to quantify this risk by examining the earliest periods corresponding to the epidemic in the Netherlands.Methods: Serum samples that had been collected from the area of highest incidence by an existing national prenatal screening programme and data from the Netherlands Perinatal Registry (PRN) on diagnosis and outcome were used. We performed indirect immunofluorescence assay to detect the presence of IgM and IgG antibodies against C. burnetii in the samples. The serological results were analyzed to determine statistical association with recorded pregnancy outcome.Results: Evaluation of serological results for 1174 women in the PRN indicated that the presence of IgM and IgG antibodies against phase II of C. burnetii was not significantly associated with preterm delivery, low birth weight, or several other outcome measures.Conclusion: The present population-based study showed no evidence of adverse pregnancy outcome among women who had antibodies to C. burnetii during early pregnancy.