Page 517 - Concise Pathology for Exam Preparation ( PDFDrive )

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Female Genital System

NORMAL ANATOMY

Uterus has three anatomical and functional regions:
1. Cervix
2. Lower uterine segment
3. Corpus

Cervix

Cervix is further divided into:
• Ectocervix (vaginal portion): It is the part of cervix that is visible from the vaginal canal.
Ectocervix is lined by nonkeratinizing stratified squamous epithelium continuous with the
vagina. The squamous epithelium converges centrally at a small opening called external
os, which is closed in nulliparous women.
• Endocervix: It is lined by columnar mucous secreting epithelium, which meets the
squamous epithelial covering at the squamocolumnar junction. The endocervical
stroma contains endocervical glands.
Progressive differentiation of the subcolumnar reserve cells determines the position of
the squamocolumnar junction. The portion of the columnar epithelium ultimately
replaced by the squamous epithelium is termed the transformation zone, which is
important clinically because this is where the precancerous and cancerous lesions develop.

Lower Uterine Segment and Corpus

Uterus has two main components—the endometrium and the myometrium. Endometrium
is composed of glands embedded in a stroma and the myometrium is composed of interwo-
ven smooth muscle bundles. The endometrial cavity (internal cavity of uterus) is slit
like and best opened by inserting a probe and cutting along with it. The endometrium is
1–5 mm wide and the myometrium is 1–2 cm wide. From each side of uterus, broad
ligament arises, which is inserted into the lateral wall of the pelvis. Fallopian tube travels in
the free border of broad ligament.

Ovaries
• Surface is lined by germinal epithelium and the average size is 4 cm 3 1.5 cm 3
1.5 cm.
• It is divided into cortex and medulla. Cortex consists of closely packed stromal cells
with a thin covering of collagen.
• Outer cortex shows follicles in varying stages of maturation. In each menstrual cycle,
one follicle develops into Graffian follicle, which is transformed into a corpus luteum
after ovulation. Senescent corpus luteum is called corpora albicans.
• Medulla consists of loosely arranged mesenchymal tissue and contains remnants of
Wolffian duct as well as round to polygonal epithelioid cells around vessels and nerves
called Hilus cells.
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