The use of endoscopy in fetal medicine

We aimed to review the state of affairs in the field of embryo-fetoscopy as well as its instrumental requirements. Today, endoscopic procedures of limited complexity are easily possible within the amniotic cavity. Embryoscopy is typically done for diagnostic purposes, such as the demonstration of external anomalies very early in pregnancy and/or obtaining embryonic tissues in recurrent miscarriages. Fetoscopy is the direct visualization of the amniotic cavity from the second trimester onwards. Its principal indications are complications of monochorionic twinning and severe congenital diaphragmatic hernia. There is level I evidence that fetoscopic laser surgery for twin- twin-transfusion syndrome is superior over amniodrainage. Fetoscopic endoluminal tracheal occlusion is done for severe diaphragmatic hernia. Whether tracheal occlusion yields better outcomes than expectant management during pregnancies is currently being investigated in a randomized trial. There are a number of less common procedures discussed as well. Overall, maternal risks of embryo-fetoscopy are minimal. The most frequent complication is rupture of the membranes and as a consequence preterm delivery. Fetal surgery seems safe and has, therefore, become a clinical reality. Although the stage of technical experimentation is over, most interventions remain investigational. Inclusion of patients into trials whenever possible should be encouraged, rather than building up casuistic experience.