Vaginal Natural Orifice Transluminal Endoscopic Surgery in a Second-trimester Pregnant Woman with an Ovarian Teratoma.

We present the first case of a pregnant woman with teratoma, who underwent vaginal natural orifice transluminal endoscopic surgery (vNOTES). Mature ovarian cystic teratomas compromise 20%-30% of all ovarian tumors. The best surgical management is still unclear, especially during pregnancy. A 21-year-old pregnant woman (gravida 1, para 0) at 14 weeks and 3 days of gestational age was admitted with an intermittent mild sharp and dull pain in her right lower abdomen when walking or moving lower limbs. Pelvic ultrasonography revealed a 5.9 cm × 5.4 cm heterogeneous mass that was suspected as a teratoma in the right adnexa. Initially, laparoendoscopic single-site ovarian cystectomy (OC) was arranged. However, the ovarian tumor was impeded by the enlarged uterus. The OC procedure was changed to vNOTES OC. The vNOTES OC was performed smoothly and the pathology confirmed the mass to be a teratoma. After the operation, she recovered well and was discharged 2 days after the operation without any complication. In conclusion, the application of vNOTES in the second-trimester pregnancy might be considered safe and effective. The vNOTES can be performed safely in selected patients and by an experienced surgeon.