L3.3.2.2: Uterus

• Uterus

  ● Has the size and shape of a pear for a woman who has never been pregnant

  ● Located in the pelvis, between the urinary bladder and rectum

  ● Site of implantation

  ● A hollow organ that functions to:

  ➔ Receive, retain, and nourish a fertilized egg, and;

  ➔ Eventually aid in childbirth
• Uterus

  ○ Structure that receives the fertilized egg.

  ○ Hollow organ that receives, retains, and nourishes a fertilized egg and, eventually, aids in childbirth.

  ○ Site of implantation, specifically, endometrium.

  ○ Located in the pelvis, situated between the urinary bladder and rectum

  ○ Size and shape of a pear, in a woman who has never been pregnant.
• UTERINE SUPPORT

  ● Broad Ligament

  ○ Suspends the uterus in the pelvis.

  ● Round Ligament

  ○ Anchors the uterus anteriorly

  ● Uterosacral Ligament

  ○ Anchors the uterus posteriorly
• PORTIONS/REGIONS OF THE UTERUS

  ● Body

  ○ Main portion

  ● Fundus

  ○ Rounded region superior to the entrance of the uterine tubes.

  ● Cervix

  ○ Narrow outlet that protrudes into the vagina.

  ○ Dilates during childbirth/delivery.
• LAYER OF THE UTERUS

  ● Endometrium

  ● Myometrium (Myo = Muscle)

  ● Perimetrium
• ● Endometrium

  ○ Inner layer or mucosa.

  ○ Site of implantation: fertilized egg is burrowed in the endometrium.

  ○ Menstruation: endometrial lining sloughs off periodically, usually about every 28 days, in response to changes in the levels of ovarian hormones in the blood.
• ● Myometrium (Myo = Muscle)

  ○ Bulky middle layer of the uterus wall.

  ○ Composed of interlacing bundles of smooth muscle.

  ○ Plays an active role during childbirth: contraction rhythmically to force the baby out of the mother’s body.
• ● Perimetrium

  ○ Visceral peritoneum or the outer serous layer of the

  uterus.