CHAPTER 19
Female Reproductive System
385
Figure 19-14A.
Umbilical cord.
H&E,
3
12; inset
3
79
The
umbilical cord
is a ropelike structure that connects the
developing fetus to the placenta. It contains two
umbilical
arteries
and one
umbilical vein
. These vessels carry oxygen
and nutrients from the mother to the fetus and waste prod-
ucts away from the fetus. The blood vessels are surrounded
by a
mucous connective tissue (Wharton jelly)
. The umbilical
arteries carry
deoxygenated fetal blood
to the placenta by
way of the chorionic arteries and the chorionic villi. After
gas and nutrient exchange with the maternal blood, the
oxygenated blood
is transported from chorionic veins to
the umbilical vein, which returns blood to the fetus.
A
Umbilical
arteries
Umbilical
vein
Mucous
connective tissue
(Wharton jelly)
Mucosa
Mucosa
Mucosa
Muscularis
Muscularis
Muscularis
Adventitia
Adventitia
Adventitia
Epithelium
Epithelium
Epithelium
Lumen
Lumen
Lumen
Lamina
Lamina
propria
propria
Lamina
propria
Ridges of the
Ridges of the
epithelium
epithelium
Ridges of the
epithelium
Lamina propria
Lamina propria
Lamina propria
Smooth muscle
Connective
tissue
Epithelium
B
Figure 19-14B.
Vagina.
H&E,
3
41; inset (
upper
)
3
63; inset (
lower
)
3
74
The
vagina
is a tubular organ that connects the cervix of the uterus to the external genitalia. The wall of the vagina consists of the
mucosa
,
muscularis
, and
adventitia
. The
mucosa
comprises a
nonkeratinized strati± ed squamous epithelium
and an underlying
lamina propria
(dense irregular connective tissue with many
elastic ± bers
). The
muscularis
contains mainly longitudinal smooth muscle and some oblique
smooth muscle bundles. The
adventitia layer
is composed of both dense connective tissue (near the muscularis) and loose connective tissue
(outer layer). The vagina is moistened by cervical secretions, and it has many sensory nerve endings in the inferior part near the entrance. The
epithelium of the vagina undergoes minimal change during the menstrual cycle. There are numerous elastic F bers in the connective tissue,
and
ridges
(folds) in the mucosa, enabling the vaginal canal to expand during sexual intercourse and during the delivery of a baby.
Funisitis
is infl ammation of the umbilical cord that often
accompanies
chorioamnionitis
(infl ammation of the fetal
membranes). ±unisitis typically occurs after 20 weeks of
gestation, often because of a bacterial infection. Neutro-
phils migrate through the umbilical vessels and may enter
the Wharton jelly. Another possible complication in preg-
nancy is an
umbilical knot
. In severe cases, obstruction of
blood supply can result in the fetal death.
The
Papanicolaou (Pap) smear
is a very important diagnostic method used for screening early signs of
cervical cancer
. Cells from the
epithelial surface of the vagina and cervix are collected by using a brush and spatula while the vagina is opened by a speculum. Exami-
nation of these sample cells provides valuable information for detecting precancerous changes that may require treatment.
Vagina
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