The uterus is the female reproductive organ that holds the fetus
When youre not pregnant, your uterus is about the size and shape of
an upside-down pear.
Non-pregnant uterine size varies with age and number of pregnancies,
but is approximately 3,5 inches long and weighs about one 6th
of a pound.
composed of two distinct anatomic regions;
is further divided into
the lower uterine segment
is a narrow cylindrical passage which connects at its lower end with
At its upper end, the cervix widens to form the lower uterine
segment (isthmus); the lower uterine segment in turn widens
into the uterine fundus.
The corpus is
the body of the uterus which grows during pregnancy to carry a
the top of the uterus on either side are the fallopian tubes
(oviducts); these tubes are continuous with the uterine cavity and
allow the passage of an egg (ova) from the ovaries to the
uterus where the egg may implant if fertilized
The thick wall
of the uterus is formed of three layers:
mucosa (endometrium) is the innermost layer that lines the
cavity of the uterus (inner
walls), nourishes the fetus during pregnancy.
Throughout the menstrual cycle, the endometrium grows progressively
thicker with a rich blood supply to prepare the uterus for potential
implantation of an embryo.
In a woman who is not pregnant,
a portion of this layer is shed
walls of the uterus
the middle and thickest layer of the uterus and is composed of
involuntary (smooth) muscle.
The myometrium contracts during menstruation to help expel the
sloughed endometrial lining and during childbirth to
allows a woman to give birth.
layer, or serosa, is a thin fibrous layer contiguous with
extrauterine connective tissue structures such as ligaments that
give mechanical support to the uterus within the pelvic cavity.
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