Anatomy: Fetus in Utero

Anatomy: Fetus in Utero


Illustration of fetus in utero

Amniotic sac. A thin-walled sac that surrounds the fetus during
pregnancy. The sac is filled with liquid made by the fetus (amniotic fluid) and
the membrane that covers the fetal side of the placenta (amnion). This protects the
fetus
from injury. It also helps to regulate the temperature of the fetus.

Anus. The opening at the end of the anal canal.

Cervix. The lower part of the uterus that extends into the
vagina. The cervix is made up of mostly fibrous tissue and muscle. It is circular
in
shape.

Fetus. An unborn baby from the 8th week after fertilization
until birth.

Placenta. An organ shaped like a flat cake. It only grows
during pregnancy. The fetus takes in oxygen, nutrients, and other substances from
the
placenta and gets rid of carbon dioxide and other wastes.

Umbilical cord. A rope-like cord connecting the fetus to the
placenta. The umbilical cord contains 2 arteries and a vein. It carries oxygen and
nutrients to the fetus and waste products away from the fetus.

Uterus. The uterus, or womb, is a hollow, pear-shaped organ in
a woman’s lower stomach between the bladder and the rectum. It sheds its lining each
month
during menstruation. A fertilized egg (ovum) becomes implanted in the uterus, and
the fetus
develops.

Vagina. The part of the female genitals behind the bladder and
in front of the rectum that forms a canal. This extends from the uterus to the vulva.