Successful diagnostic and therapeutic intrauterine fetal interventions by natural orifice transluminal endoscopic surgery (with videos).

Background: Despite advances in the development of fetal surgery, morbidity and mortality are substantial. A natural orifice transluminal endoscopic surgery (NOTES)-guided approach to the gravid uterus may offer a less-invasive technique.

Objective: To assess the feasibility of NOTES for diagnostic and therapeutic intrauterine fetal interventions.

Setting: Survival and nonsurvival experiments on pregnant sheep.

Design And Intervention: Nonsurvival experiments performed in 2 pregnant sheep (80-110 days' gestation). A third ewe underwent NOTES and survived for 4 weeks. Transgastric (nonsurvival ewes) and transvaginal (1 nonsurvival and the survived ewe) peritoneoscopy was performed after standard needle-knife entry into the peritoneal cavity. Endoscopic access to the gravid uterus was assessed. EUS-guided, transuterine injection of saline solution into the fetal cardiac ventricle and vessels was attempted in all.

Main Outcome Measurements: Feasibility of NOTES- and EUS-guided intervention in a pregnant animal model, visibility of fetal parts via EUS compared with transabdominal US.

Results: Entry into the peritoneal cavity was achieved in each ewe. Access to and complete visualization of the gravid uterus were successful once within the abdominal cavity. Visualization of the fetal parts and the placental cotyledons by EUS was achieved in all animals. EUS-guided amniocenteses and transuterine intracardiac and intravascular injection of saline were successful. There were no complications or preterm delivery after the procedures.

Limitations: Animal model.

Conclusions: NOTES is technically feasible in the pregnant ewe. Intraperitoneal EUS via a NOTES approach provides excellent access and visualization of the intrauterine cavity and fetal parts.