Table 2

Gestational age parameters for Danish pregnant women according to antibodies against C.burnetii, immunofluorescence antibody test (IFA)
IFA positive for C. burnetii antibodies (n = 169) IFA negative for C. burnetii antibodies (n = 687) Measures of association
Crude Adjusted
Spontaneous abortion < 22 weeks (n = 8) 2 (1.2%) 6 (0.9%) OR: 1.4 1.5 (95% CI: 0.3–7.6)*
Preterm birth (< week 37) (n = 41) 3 (1.8%) 38 (5.5%) OR: 0.3 OR: 0.4 (95% CI: 0.1–1.1)**
Gestational age (>week 36 + 6) (n = 806****) Median gestational age (interquartile range) 40 weeks 3 days (39 w, 3d; 41 w,1 d) 40 w, 2 days (39w, 3d; 41w,1d) Mean difference in days*** 0.91 days 1.2 days (−0.4– +2.7)**

*adjusted for age **adjusted for smoking, age and gravidity *** babies of IFA positive mothers were older **** of which 163 were seropositive and 643 seronegative.

Nielsen et al.

Nielsen et al. BMC Infectious Diseases 2013 13:87   doi:10.1186/1471-2334-13-87

Open Data