Introduction Medical interventions should only be offered if there is evidence that they help the patient. At present, there is consensus that their effectiveness should be evaluated before incorporation into guidelines. Since the inception of fetal medicine as a subspecialty and the application of in-utero treatments for fetal therapy, there have been cohort studies presented. Initially these cohort series (mainly retrospective) were based on experiences from tertiary centers but in the last five to ten years there has been more of a focus on “population-based” cohort studies that at least have accurate denominator data from which to calculate outcomes. Critical appraisal of the literature and appraisal of fetal therapy has been aided by performing systematic reviews and, where practicable, meta-analysis of outcomes. However, although such methods are informative they summate evidence from relatively small and often heterogeneous case cohort studies. The randomized clinical trial is considered to be the best research tool to evaluate the effectiveness of medical interventions, and is the widely acknowledged design of choice for evaluating medical and surgical treatments [1 – 3].
The future: Fetal therapy and translational studies: Global alignment, coordination, and collaboration in perinatal research: The global obstetrics network (GONet) initiative / Mol, B. W.; Kilby, M. D.; Asztalos, E.; Dekker, G.; Facchinetti, F.; Metin Gulmezoglu, A.; Magee, L.; Morris, J.; Norman, J.; Poston, L.; Saade, G.; Shennan, A.; Thom, E.; Von Dadelszen, P.; Leung, T. Y.; Merialdi, M.; Alfirevic, Z.. - 9781107012134:(2009), pp. 433-439. [10.1017/CBO9780511997778.044]