title: Sonographic findings in acute urinary retention secondary to retroverted gravid uterus: pathophysiology and preventive measures.
abstract: OBJECTIVE
  To explore the pathophysiology of acute urinary retention in women with a retroverted gravid uterus and to suggest measures to prevent its recurrence.
  
  
  METHODS
  In five women with a retroverted gravid uterus and acute urinary retention necessitating catheterization, the morphology of the genitourinary system was assessed by using transabdominal, transvaginal and introital sonography.
  
  
  RESULTS
  In the supine resting position, the cervix was displaced superiorly and anteriorly by the impacted and retroverted uterus so that it compressed the lower bladder, leading to obstruction of the internal urethral orifice. The upper bladder extended superiorly and overlay the uterus. During straining, urethral motion was not limited and there was an average rotational angle of the bladder neck of 32 degrees, ranging from 21 degrees to 44 degrees. Increasing abdominal pressure further compressed the lower bladder. Measures suggested to the women for the prevention of urinary retention included limiting fluid intake before sleep, changing from the supine to the prone position before getting up and avoiding a Valsalva maneuver but performing a Credé maneuver during voiding. In all except one case these measures successfully prevented recurrence.
  
  
  CONCLUSIONS
  Acute urinary retention secondary to a retroverted gravid uterus is caused by a displaced cervix compressing the lower bladder and interfering with drainage to the urethra. The urethra itself is not compressed or distorted. Understanding the pathophysiology of the lower urinary tract may allow maneuvers which prevent acute urinary retention.
authors.affiliation: Division of Urogynecology, Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei Medical University, Taiwan, ROC. yangjm0211@hotmail.com
authors.forename: J-M
authors.initials: JM
authors.lastname: Yang
authors.forename: W-C
authors.initials: WC
authors.lastname: Huang
mesh_terms: D000208:Acute Disease; D000328:Adult; D005260:Female; D006801:Humans; D011187:Posture; D011247:Pregnancy; D011248:Pregnancy Complications / Q000000981:diagnostic imaging / Q000209:etiology* / Q000628:therapy; D011262:Pregnancy Trimester, Second; D014463:Ultrasonography; D014521:Urethra / Q000000981:diagnostic imaging; D001743:Urinary Bladder / Q000000981:diagnostic imaging*; D016055:Urinary Retention / Q000000981:diagnostic imaging / Q000209:etiology* / Q000628:therapy; D019687:Uterine Inversion / Q000150:complications* / Q000000981:diagnostic imaging / Q000628:therapy