Medical management of recurrent miscarriage—evidence-based approach

Various medical interventions have been used to improve the live birth rate in recurrent miscarriage. However, most often the indication for intervention was 3 or more miscarriages up to 20 weeks. Although this is a heterogeneous group of patients with many causes of miscarriage, randomized trials and meta-analyses have tried to provide evidence of efficacy. In this presentation, the efficacy of hormone supplements, paternal leucocyte immunization and intravenous immunoglobulin are assessed. The efficacy of anticoagulants for antiphospholipid syndrome and hereditary thrombophilias are also discussed. There is Grade I evidence for the efficacy of all of these, but there is also Grade I evidence against some of these interventions. Pregnancy loss can have maternal or fetal causes, such as chromosomal aberrations. If the cause is unknown, the results are confounded. If treatment for a maternal cause is tested on a patient losing a chromosomally abnormal embryo, it will be ineffective. Similarly, there are patients with good and poor prognoses. If treatment is given to a patient with a good prognosis, it will be ineffective. Hence, it is necessary to define a cohort of patients with a poor prognosis, and to reach an accurate diagnosis. At that point, a valid randomized control trial can be performed. At present, evidence-based medicine can only determine that a treatment is effective within the cohort of patients studied. It cannot provide information of efficacy in subgroups. Even if there is no evidence of efficacy, present trials cannot show evidence of inefficacy.