Intrauterine infection may be a major cause of stillbirth in Sweden

Aim of the study. To investigate intrauterine infection as a cause for unex plained stillbirth. Methods. Chorioamnionitis was studied in a material of stillbirths (117 sub jects from the years 1985-1994) from a region in the south Sweden. Control material (126 alive and healthy newborns and with healthy mothers) was gath ered from the same region. Results. Chorioamnionitis was a common diagnosis both with stillbirths and 'healthy' deliveries (82 and 68%, respectively). Extension of the inflammat ion to decidua basalis was seven times more common among stillbirths than a mong controls (odds ratio 7.2, confidence interval 2.8-21.9). The most comm on bacteria found at cultures were Escherichia coli, Coagulase negative sta phylococcus, Enterococcus faecalis and group B Streptococcus. The risk for stillbirth was doubled if both inflammation and bacteria were present (odds ratio 2.3, confidence interval 0.92-5.8). Meconium discharge was more comm on among stillbirths than controls (odds ratio=4.7, confidence interval 1.7 -14). There were no differences in any respect regarding macerated and non- macerated stillbirths. Our findings are similar to the results from studies in developing countries except for the higher incidence of stillbirths in such countries. Conclusions. Thus, a large part of otherwise unexplained stillbirths might be due to ascending infections.