Objective: To present a case of obstructed hemivagina and ipsilateral renal anomaly (OHVIRA) syndrome complicated with pyometra and explain tips and tricks for laparoscopic hemihysterectomy., Design: A step-by-step explanation of the technique with the use of video (Canadian Task Force Classification III). Patient consent and Institutional Review Board approval were obtained., Setting: OHVIRA syndrome is characterized by the triad of uterovaginal duplication, obstructed hemivagina, and ipsilateral renal agenesis (1). Patients with OHVIRA syndrome usually present with dysmenorrhea and a vaginal or a pelvic mass. Renal, uterine, and vaginal pathologies can be diagnosed with the use of ultrasonography and magnetic resonance imaging (MRI) (2). In cases in which the diagnosis is not delayed, treatment consists of vaginal septostomy (3). Delayed diagnosis may lead to pelvic infections in patients with microperforations in the septum, which may lead to abscess formation, pelvic inflammatory disease, pyometra, and subsequent need for hemihysterectomy and adnexectomy (4)., Patient(s): A 21-year-old G2 P2 patient who had a history of hospitalization with the diagnosis of tubo-ovarian abscess three times previously presented to the emergency department with pelvic pain, nausea, high fever, and malodorous vaginal discharge. On physical examination, a pelvic abscess draining to the left vaginal wall and a 10-12-cm left adnexal mass were noticed. A diagnosis of OHVIRA syndrome and pyometra was made after evaluation of ultrasonographic and MRI findings. Longitudinal vaginal septum excision and drainage of the abscess was performed. Ten cubic centimeters of purulent abscess material was drained by incising the left vaginal wall. However, the mass extending from the left vaginal wall to the left adnexal area could not be drained. On hysteroscopy, no cervix was visualized belonging to the obstructed hemivagina and the left uterine cavity could not be entered. On reexamination of the MR images, the presence of a transverse vaginal septum overlying the left hemivagina was detected, preventing access to the left hemiuterine cavity. The transverse vaginal septum could have been excised and the pyometra drained; however, owing to the presence of chronic pelvic pain and dyspareunia, and a history of three failed previous attempts at treatment, the decision to perform hemihysterectomy was made., Intervention(s): A laparoscopic hemihysterectomy was performed in the patient, who was diagnosed as having OHVIRA syndrome complicated with pyometra. Patient consent and Institutional Review Board approval were obtained for this report., Main Outcome Measure(s): On laparoscopy, the left hemiuterus on the same side as the obstructed hemivagina appeared three to four times larger than the normal hemiuterus, in which two pregnancies had occurred, and dense adhesions were present between this hemiuterus and the bowel. The left hemiuterus was densely adherent to the pelvic side wall. Laparoscopic hemihysterectomy was performed. A monofilament barbed suture were used for the repair of the paracervical area and left hemivagina. A transverse septum and cervical atresia was noticed at the distal end of the left hemiuterus. The surgical challenges encountered during treatment of this case were the difficulty in recognizing anatomic structures owing to chronic inflammatory changes, dissecting dense adhesions without injuring neighboring pelvic organs, providing adequate hemostasis during dissection of fragile and hemorrhagic tissues, gaining optimal visualization of the surgical field owing to hampered hemostasis, obtaining adequate exposure of the surgical site owing to the inability to use a uterine manipulator, and the difficulty in dissecting the left hemiuterus without damaging the right hemiuterus for fertility preservation. The ultrasonic scalpel is an energy modality that is known to cause the least amount of collateral thermal tissue damage. In the present case, an ultrasonic scalpel was used to dissect dense adhesions between the left hemiuterus and the urinary bladder to minimize the risk of thermal injury to the urinary bladder. The ultrasonic scalpel was also used when dissecting the unhealthy hemiuterus from the healthy hemiuterus owing to its ergonomic tip and to avoid thermal damage to the cervix of the healthy hemiuterus. In areas of dense adhesions and distorted anatomy, the broad tips of bipolar forceps are also helpful for blunt dissection and the creation of tissue planes, and it is also used for effective concomitant hemostasis. A vessel sealer is the most appropriate energy modality for providing effective hemostasis during dissection of the uterine artery while causing minimal collateral tissue damage (5, 6). When deciding the kind of energy modality to be used during operative laparoscopy, the source that minimized thermal injury while providing optimal hemostasis was preferred. Furthermore, additional features such as rotation, dissection, grasping, and the ergonomics of the tip of the device were also considered when choosing the energy source to be used., Result(s): The patient was discharged 48 hours postoperatively with no complications. No symptoms of pelvic pain, dysmenorrhea, and dyspareunia were present at the end of the third month after surgery., Conclusion(s): Understanding the exact nature of the uterine anomaly before hemihysterectomy is of paramount importance for a successful surgery. Laparoscopy is a safe and effective treatment modality even in the presence of dense pelvic adhesions and distorted pelvic anatomy., (Copyright © 2019 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)