Chronic intervillositis of the placenta: A systematic review

OBJECTIVE: Chronic intervillositis of the placenta is known to be associated with poor reproductive outcome and a high risk of recurrence. The aims of the present study were to quantify the risk of recurrence of chronic intervillositis in subsequent pregnancies, to explore if there are possible interventions and to assess the success of interventions. METHODS: Systematic review of published literature using published guidelines. RESULTS: No randomised controlled trials were identified. Sixty-one papers, published between 1977 and 2009 were identified after abstract screening but only 6 studies could be included in the systematic review. From the 6 selected studies, 69 pregnancies at gestational age of 14 weeks or over, with a histopathologic diagnosis of chronic intervillositis were available for analysis. The rate of intrauterine growth restriction in the study population was 66.7%, the overall rate of livebirth was 53.6%. In 16/20 (80.0%) cases recurrence of CI was confirmed at histopathology. The livebirth rate reported with treatment was 30.8% against 58.9% without treatment (RR=0.47, 95% CI=0.2-1.1). This difference was not statistically significant. CONCLUSIONS: Chronic intervillositis has a high (80.0%) recurrence risk. In pregnancies reaching 14 weeks, the chance of a livebirth is 53.6%. The livebirth rate reported with treatment was 30.8% against 58.9% without treatment (RR=0.47, 95% CI=0.2-1.1). This difference was not statistically significant. Intervention with drug therapy is of no demonstrable benefit, and may even be harmful.