Uterine isthmus

{{Short description|Inferior-posterior part of uterus}}

{{Distinguish|Isthmus of uterine tube}}

{{Infobox anatomy

| Name = Uterine isthmus

| Latin = isthmus uteri

| Image = Illu female pelvis.jpg

| Caption = Uterine isthmus labeled at 12

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The uterine isthmus is the inferior-posterior part of uterus, on its cervical end — here, the uterine muscle (myometrium) is narrower and thinner. It connects the body and cervix.{{cite book|title=Introductory Maternity & Pediatric Nursing|author=N. Jayne Klossner and Nancy T. Hatfield|pages=[https://archive.org/details/introductorymate00klos/page/56 56]|publisher=Lippincott Williams & Wilkins|year=2006|isbn=9780781736909|url-access=registration|url=https://archive.org/details/introductorymate00klos/page/56}}

The uterine isthmus can become more compressibile in pregnancy, which is a finding known as Hegar's sign.