Objective: In a previous questionnaire study, more breast cancers were reported by women with intrahepatic cholestasis of pregnancy (ICP) than by the controls. The aim of this study was to establish whether ICP is associated with cancer in the Finnish Cancer Registry data, the study population being the same cohort as in the questionnaire study.
Methods: The study population comprised 571 women with ICP in at least one pregnancy and 1,333 controls from Tampere University Hospital in Finland during 1969–1988. The cancer data were obtained from the Finnish Cancer Registry. The cancers were classified by ICD-O-3 and diagnosed during the period 1953−2013.
Results: In the ICP group, the odds ratio of cancers (OR 1.26, 95% CI 0.96–1.64), and breast cancer in particular (OR 1.36, 95% CI 0.91–2.03), was slightly higher than in the control group. Seven percent of the ICP group and 5.3% of the control group had breast cancer.
Conclusion: Based on this study there is not a significant association between ICP and cancer. Earlier observation in the questionnaire study regarding association between ICP and breast cancer cannot be confirmed by this registry based study.